mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
synced 2025-08-26 21:52:20 +00:00
loongarch-next
92 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Linus Torvalds
|
63eb28bb14 |
ARM:
- Host driver for GICv5, the next generation interrupt controller for arm64, including support for interrupt routing, MSIs, interrupt translation and wired interrupts. - Use FEAT_GCIE_LEGACY on GICv5 systems to virtualize GICv3 VMs on GICv5 hardware, leveraging the legacy VGIC interface. - Userspace control of the 'nASSGIcap' GICv3 feature, allowing userspace to disable support for SGIs w/o an active state on hardware that previously advertised it unconditionally. - Map supporting endpoints with cacheable memory attributes on systems with FEAT_S2FWB and DIC where KVM no longer needs to perform cache maintenance on the address range. - Nested support for FEAT_RAS and FEAT_DoubleFault2, allowing the guest hypervisor to inject external aborts into an L2 VM and take traps of masked external aborts to the hypervisor. - Convert more system register sanitization to the config-driven implementation. - Fixes to the visibility of EL2 registers, namely making VGICv3 system registers accessible through the VGIC device instead of the ONE_REG vCPU ioctls. - Various cleanups and minor fixes. LoongArch: - Add stat information for in-kernel irqchip - Add tracepoints for CPUCFG and CSR emulation exits - Enhance in-kernel irqchip emulation - Various cleanups. RISC-V: - Enable ring-based dirty memory tracking - Improve perf kvm stat to report interrupt events - Delegate illegal instruction trap to VS-mode - MMU improvements related to upcoming nested virtualization s390x - Fixes x86: - Add CONFIG_KVM_IOAPIC for x86 to allow disabling support for I/O APIC, PIC, and PIT emulation at compile time. - Share device posted IRQ code between SVM and VMX and harden it against bugs and runtime errors. - Use vcpu_idx, not vcpu_id, for GA log tag/metadata, to make lookups O(1) instead of O(n). - For MMIO stale data mitigation, track whether or not a vCPU has access to (host) MMIO based on whether the page tables have MMIO pfns mapped; using VFIO is prone to false negatives - Rework the MSR interception code so that the SVM and VMX APIs are more or less identical. - Recalculate all MSR intercepts from scratch on MSR filter changes, instead of maintaining shadow bitmaps. - Advertise support for LKGS (Load Kernel GS base), a new instruction that's loosely related to FRED, but is supported and enumerated independently. - Fix a user-triggerable WARN that syzkaller found by setting the vCPU in INIT_RECEIVED state (aka wait-for-SIPI), and then putting the vCPU into VMX Root Mode (post-VMXON). Trying to detect every possible path leading to architecturally forbidden states is hard and even risks breaking userspace (if it goes from valid to valid state but passes through invalid states), so just wait until KVM_RUN to detect that the vCPU state isn't allowed. - Add KVM_X86_DISABLE_EXITS_APERFMPERF to allow disabling interception of APERF/MPERF reads, so that a "properly" configured VM can access APERF/MPERF. This has many caveats (APERF/MPERF cannot be zeroed on vCPU creation or saved/restored on suspend and resume, or preserved over thread migration let alone VM migration) but can be useful whenever you're interested in letting Linux guests see the effective physical CPU frequency in /proc/cpuinfo. - Reject KVM_SET_TSC_KHZ for vm file descriptors if vCPUs have been created, as there's no known use case for changing the default frequency for other VM types and it goes counter to the very reason why the ioctl was added to the vm file descriptor. And also, there would be no way to make it work for confidential VMs with a "secure" TSC, so kill two birds with one stone. - Dynamically allocation the shadow MMU's hashed page list, and defer allocating the hashed list until it's actually needed (the TDP MMU doesn't use the list). - Extract many of KVM's helpers for accessing architectural local APIC state to common x86 so that they can be shared by guest-side code for Secure AVIC. - Various cleanups and fixes. x86 (Intel): - Preserve the host's DEBUGCTL.FREEZE_IN_SMM when running the guest. Failure to honor FREEZE_IN_SMM can leak host state into guests. - Explicitly check vmcs12.GUEST_DEBUGCTL on nested VM-Enter to prevent L1 from running L2 with features that KVM doesn't support, e.g. BTF. x86 (AMD): - WARN and reject loading kvm-amd.ko instead of panicking the kernel if the nested SVM MSRPM offsets tracker can't handle an MSR (which is pretty much a static condition and therefore should never happen, but still). - Fix a variety of flaws and bugs in the AVIC device posted IRQ code. - Inhibit AVIC if a vCPU's ID is too big (relative to what hardware supports) instead of rejecting vCPU creation. - Extend enable_ipiv module param support to SVM, by simply leaving IsRunning clear in the vCPU's physical ID table entry. - Disable IPI virtualization, via enable_ipiv, if the CPU is affected by erratum #1235, to allow (safely) enabling AVIC on such CPUs. - Request GA Log interrupts if and only if the target vCPU is blocking, i.e. only if KVM needs a notification in order to wake the vCPU. - Intercept SPEC_CTRL on AMD if the MSR shouldn't exist according to the vCPU's CPUID model. - Accept any SNP policy that is accepted by the firmware with respect to SMT and single-socket restrictions. An incompatible policy doesn't put the kernel at risk in any way, so there's no reason for KVM to care. - Drop a superfluous WBINVD (on all CPUs!) when destroying a VM and use WBNOINVD instead of WBINVD when possible for SEV cache maintenance. - When reclaiming memory from an SEV guest, only do cache flushes on CPUs that have ever run a vCPU for the guest, i.e. don't flush the caches for CPUs that can't possibly have cache lines with dirty, encrypted data. Generic: - Rework irqbypass to track/match producers and consumers via an xarray instead of a linked list. Using a linked list leads to O(n^2) insertion times, which is hugely problematic for use cases that create large numbers of VMs. Such use cases typically don't actually use irqbypass, but eliminating the pointless registration is a future problem to solve as it likely requires new uAPI. - Track irqbypass's "token" as "struct eventfd_ctx *" instead of a "void *", to avoid making a simple concept unnecessarily difficult to understand. - Decouple device posted IRQs from VFIO device assignment, as binding a VM to a VFIO group is not a requirement for enabling device posted IRQs. - Clean up and document/comment the irqfd assignment code. - Disallow binding multiple irqfds to an eventfd with a priority waiter, i.e. ensure an eventfd is bound to at most one irqfd through the entire host, and add a selftest to verify eventfd:irqfd bindings are globally unique. - Add a tracepoint for KVM_SET_MEMORY_ATTRIBUTES to help debug issues related to private <=> shared memory conversions. - Drop guest_memfd's .getattr() implementation as the VFS layer will call generic_fillattr() if inode_operations.getattr is NULL. - Fix issues with dirty ring harvesting where KVM doesn't bound the processing of entries in any way, which allows userspace to keep KVM in a tight loop indefinitely. - Kill off kvm_arch_{start,end}_assignment() and x86's associated tracking, now that KVM no longer uses assigned_device_count as a heuristic for either irqbypass usage or MDS mitigation. Selftests: - Fix a comment typo. - Verify KVM is loaded when getting any KVM module param so that attempting to run a selftest without kvm.ko loaded results in a SKIP message about KVM not being loaded/enabled (versus some random parameter not existing). - Skip tests that hit EACCES when attempting to access a file, and rpint a "Root required?" help message. In most cases, the test just needs to be run with elevated permissions. -----BEGIN PGP SIGNATURE----- iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmiKXMgUHHBib256aW5p QHJlZGhhdC5jb20ACgkQv/vSX3jHroMhMQf/QDhC/CP1aGXph2whuyeD2NMqPKiU 9KdnDNST+ftPwjg9QxZ9mTaa8zeVz/wly6XlxD9OQHy+opM1wcys3k0GZAFFEEQm YrThgURdzEZ3nwJZgb+m0t4wjJQtpiFIBwAf7qq6z1VrqQBEmHXJ/8QxGuqO+BNC j5q/X+q6KZwehKI6lgFBrrOKWFaxqhnRAYfW6rGBxRXxzTJuna37fvDpodQnNceN zOiq+avfriUMArTXTqOteJNKU0229HjiPSnjILLnFQ+B3akBlwNG0jk7TMaAKR6q IZWG1EIS9q1BAkGXaw6DE1y6d/YwtXCR5qgAIkiGwaPt5yj9Oj6kRN2Ytw== =j2At -----END PGP SIGNATURE----- Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm Pull kvm updates from Paolo Bonzini: "ARM: - Host driver for GICv5, the next generation interrupt controller for arm64, including support for interrupt routing, MSIs, interrupt translation and wired interrupts - Use FEAT_GCIE_LEGACY on GICv5 systems to virtualize GICv3 VMs on GICv5 hardware, leveraging the legacy VGIC interface - Userspace control of the 'nASSGIcap' GICv3 feature, allowing userspace to disable support for SGIs w/o an active state on hardware that previously advertised it unconditionally - Map supporting endpoints with cacheable memory attributes on systems with FEAT_S2FWB and DIC where KVM no longer needs to perform cache maintenance on the address range - Nested support for FEAT_RAS and FEAT_DoubleFault2, allowing the guest hypervisor to inject external aborts into an L2 VM and take traps of masked external aborts to the hypervisor - Convert more system register sanitization to the config-driven implementation - Fixes to the visibility of EL2 registers, namely making VGICv3 system registers accessible through the VGIC device instead of the ONE_REG vCPU ioctls - Various cleanups and minor fixes LoongArch: - Add stat information for in-kernel irqchip - Add tracepoints for CPUCFG and CSR emulation exits - Enhance in-kernel irqchip emulation - Various cleanups RISC-V: - Enable ring-based dirty memory tracking - Improve perf kvm stat to report interrupt events - Delegate illegal instruction trap to VS-mode - MMU improvements related to upcoming nested virtualization s390x - Fixes x86: - Add CONFIG_KVM_IOAPIC for x86 to allow disabling support for I/O APIC, PIC, and PIT emulation at compile time - Share device posted IRQ code between SVM and VMX and harden it against bugs and runtime errors - Use vcpu_idx, not vcpu_id, for GA log tag/metadata, to make lookups O(1) instead of O(n) - For MMIO stale data mitigation, track whether or not a vCPU has access to (host) MMIO based on whether the page tables have MMIO pfns mapped; using VFIO is prone to false negatives - Rework the MSR interception code so that the SVM and VMX APIs are more or less identical - Recalculate all MSR intercepts from scratch on MSR filter changes, instead of maintaining shadow bitmaps - Advertise support for LKGS (Load Kernel GS base), a new instruction that's loosely related to FRED, but is supported and enumerated independently - Fix a user-triggerable WARN that syzkaller found by setting the vCPU in INIT_RECEIVED state (aka wait-for-SIPI), and then putting the vCPU into VMX Root Mode (post-VMXON). Trying to detect every possible path leading to architecturally forbidden states is hard and even risks breaking userspace (if it goes from valid to valid state but passes through invalid states), so just wait until KVM_RUN to detect that the vCPU state isn't allowed - Add KVM_X86_DISABLE_EXITS_APERFMPERF to allow disabling interception of APERF/MPERF reads, so that a "properly" configured VM can access APERF/MPERF. This has many caveats (APERF/MPERF cannot be zeroed on vCPU creation or saved/restored on suspend and resume, or preserved over thread migration let alone VM migration) but can be useful whenever you're interested in letting Linux guests see the effective physical CPU frequency in /proc/cpuinfo - Reject KVM_SET_TSC_KHZ for vm file descriptors if vCPUs have been created, as there's no known use case for changing the default frequency for other VM types and it goes counter to the very reason why the ioctl was added to the vm file descriptor. And also, there would be no way to make it work for confidential VMs with a "secure" TSC, so kill two birds with one stone - Dynamically allocation the shadow MMU's hashed page list, and defer allocating the hashed list until it's actually needed (the TDP MMU doesn't use the list) - Extract many of KVM's helpers for accessing architectural local APIC state to common x86 so that they can be shared by guest-side code for Secure AVIC - Various cleanups and fixes x86 (Intel): - Preserve the host's DEBUGCTL.FREEZE_IN_SMM when running the guest. Failure to honor FREEZE_IN_SMM can leak host state into guests - Explicitly check vmcs12.GUEST_DEBUGCTL on nested VM-Enter to prevent L1 from running L2 with features that KVM doesn't support, e.g. BTF x86 (AMD): - WARN and reject loading kvm-amd.ko instead of panicking the kernel if the nested SVM MSRPM offsets tracker can't handle an MSR (which is pretty much a static condition and therefore should never happen, but still) - Fix a variety of flaws and bugs in the AVIC device posted IRQ code - Inhibit AVIC if a vCPU's ID is too big (relative to what hardware supports) instead of rejecting vCPU creation - Extend enable_ipiv module param support to SVM, by simply leaving IsRunning clear in the vCPU's physical ID table entry - Disable IPI virtualization, via enable_ipiv, if the CPU is affected by erratum #1235, to allow (safely) enabling AVIC on such CPUs - Request GA Log interrupts if and only if the target vCPU is blocking, i.e. only if KVM needs a notification in order to wake the vCPU - Intercept SPEC_CTRL on AMD if the MSR shouldn't exist according to the vCPU's CPUID model - Accept any SNP policy that is accepted by the firmware with respect to SMT and single-socket restrictions. An incompatible policy doesn't put the kernel at risk in any way, so there's no reason for KVM to care - Drop a superfluous WBINVD (on all CPUs!) when destroying a VM and use WBNOINVD instead of WBINVD when possible for SEV cache maintenance - When reclaiming memory from an SEV guest, only do cache flushes on CPUs that have ever run a vCPU for the guest, i.e. don't flush the caches for CPUs that can't possibly have cache lines with dirty, encrypted data Generic: - Rework irqbypass to track/match producers and consumers via an xarray instead of a linked list. Using a linked list leads to O(n^2) insertion times, which is hugely problematic for use cases that create large numbers of VMs. Such use cases typically don't actually use irqbypass, but eliminating the pointless registration is a future problem to solve as it likely requires new uAPI - Track irqbypass's "token" as "struct eventfd_ctx *" instead of a "void *", to avoid making a simple concept unnecessarily difficult to understand - Decouple device posted IRQs from VFIO device assignment, as binding a VM to a VFIO group is not a requirement for enabling device posted IRQs - Clean up and document/comment the irqfd assignment code - Disallow binding multiple irqfds to an eventfd with a priority waiter, i.e. ensure an eventfd is bound to at most one irqfd through the entire host, and add a selftest to verify eventfd:irqfd bindings are globally unique - Add a tracepoint for KVM_SET_MEMORY_ATTRIBUTES to help debug issues related to private <=> shared memory conversions - Drop guest_memfd's .getattr() implementation as the VFS layer will call generic_fillattr() if inode_operations.getattr is NULL - Fix issues with dirty ring harvesting where KVM doesn't bound the processing of entries in any way, which allows userspace to keep KVM in a tight loop indefinitely - Kill off kvm_arch_{start,end}_assignment() and x86's associated tracking, now that KVM no longer uses assigned_device_count as a heuristic for either irqbypass usage or MDS mitigation Selftests: - Fix a comment typo - Verify KVM is loaded when getting any KVM module param so that attempting to run a selftest without kvm.ko loaded results in a SKIP message about KVM not being loaded/enabled (versus some random parameter not existing) - Skip tests that hit EACCES when attempting to access a file, and print a "Root required?" help message. In most cases, the test just needs to be run with elevated permissions" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (340 commits) Documentation: KVM: Use unordered list for pre-init VGIC registers RISC-V: KVM: Avoid re-acquiring memslot in kvm_riscv_gstage_map() RISC-V: KVM: Use find_vma_intersection() to search for intersecting VMAs RISC-V: perf/kvm: Add reporting of interrupt events RISC-V: KVM: Enable ring-based dirty memory tracking RISC-V: KVM: Fix inclusion of Smnpm in the guest ISA bitmap RISC-V: KVM: Delegate illegal instruction fault to VS mode RISC-V: KVM: Pass VMID as parameter to kvm_riscv_hfence_xyz() APIs RISC-V: KVM: Factor-out g-stage page table management RISC-V: KVM: Add vmid field to struct kvm_riscv_hfence RISC-V: KVM: Introduce struct kvm_gstage_mapping RISC-V: KVM: Factor-out MMU related declarations into separate headers RISC-V: KVM: Use ncsr_xyz() in kvm_riscv_vcpu_trap_redirect() RISC-V: KVM: Implement kvm_arch_flush_remote_tlbs_range() RISC-V: KVM: Don't flush TLB when PTE is unchanged RISC-V: KVM: Replace KVM_REQ_HFENCE_GVMA_VMID_ALL with KVM_REQ_TLB_FLUSH RISC-V: KVM: Rename and move kvm_riscv_local_tlb_sanitize() RISC-V: KVM: Drop the return value of kvm_riscv_vcpu_aia_init() RISC-V: KVM: Check kvm_riscv_vcpu_alloc_vector_context() return value KVM: arm64: selftests: Add FEAT_RAS EL2 registers to get-reg-list ... |
||
|
Mark Rutland
|
ee4a2e08c1 |
entry: Add arch_in_rcu_eqs()
All architectures have an interruptible RCU extended quiescent state (EQS) as part of their idle sequences, where interrupts can occur without RCU watching. Entry code must account for this and wake RCU as necessary; the common entry code deals with this in irqentry_enter() by treating any interrupt from an idle thread as potentially having occurred within an EQS and waking RCU for the duration of the interrupt via rcu_irq_enter() .. rcu_irq_exit(). Some architectures may have other interruptible EQSs which require similar treatment. For example, on s390 it is necessary to enable interrupts around guest entry in the middle of a period where core KVM code has entered an EQS. So that architectures can wake RCU in these cases, this patch adds a new arch_in_rcu_eqs() hook to the common entry code which is checked in addition to the existing is_idle_thread() check, with RCU woken if either returns true. A default implementation is provided which always returns false, which suffices for most architectures. As no architectures currently implement arch_in_rcu_eqs(), there should be no functional change as a result of this patch alone. A subsequent patch will add an s390 implementation to fix a latent bug with missing RCU wakeups. [ajd@linux.ibm.com: rebase, fix commit message] Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Claudio Imbrenda <imbrenda@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Janosch Frank <frankja@linux.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com> Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Link: https://lore.kernel.org/r/20250708092742.104309-2-ajd@linux.ibm.com Signed-off-by: Janosch Frank <frankja@linux.ibm.com> Message-ID: <20250708092742.104309-2-ajd@linux.ibm.com> |
||
|
Thomas Gleixner
|
5173ac2dc8 |
Prerequisite for ARM[64] generic entry conversion
-----BEGIN PGP SIGNATURE----- iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmhizyYTHHRnbHhAbGlu dXRyb25peC5kZQAKCRCmGPVMDXSYoYXaD/4+Y3E697PG/rWlVZwsOhGdxUO2SZL/ eXlCmndSqtKcRluh0HAl9Y0XL5cfZ+LslonfxFYH25LQcVBLaUkB4y1YSXuob6N1 Czh1I5cRzLXMB0MzS0tzjjRZnoFTPzXfSj+WMLy7/UqfAflMYoGSPMnFQkdnf6gV kBoLFKctAhxMZNoqzEShXXsN6MzFj6LVI/VPaXKIw9tRe8W8QM4JTikb2QPw2ZAx K+PxH4NFmMjmt9KtAeZdAdmcOWlF7nil/DHbefEjsQOStcXQO+MkdozDjtW65/TY E7Brat7wPgSmUrt8+jgJVE7f38proLkYPfRrOJccumBD+XeMVu2XUnfhWqRENzoE 7v7Xb3ce3c6ROEZGSzDP1rakWqPytoBX0+70POkiQQYIIyCyXFwMOPju3vlWMwqN tFGOw75mbdG+X2otZpoQcWZPAPRqdqwmAEl8LR4cJnRh+I2R6oo/K0KkPcM9+JJN L1YnEQk1w/wsIcnFkxWOUdYwMuJLvecli7gKaVs6J2AGzLvJVMYpWglSlhGzrufC ZMEhEKgDJYU9QhftBBqul/tmi+JRbAjIzTN1zrBPntQ2CYyLjXtsCKQsDvqxaErI uc0JYxjv3/D0sjzqrIHZfZHv04XtZ2kTnkhBiD7zGJ469LZDTDXctd8m9rgzYSDi Uho970FEvl18yQ== =IUBY -----END PGP SIGNATURE----- Merge tag 'entry-split-for-arm' into core/entry Prerequisite for ARM[64] generic entry conversion Merge it into the entry branch so further changes can be based on it. |
||
|
Jinjie Ruan
|
a70e9f647f |
entry: Split generic entry into generic exception and syscall entry
Currently CONFIG_GENERIC_ENTRY enables both the generic exception entry logic and the generic syscall entry logic, which are otherwise loosely coupled. Introduce separate config options for these so that architectures can select the two independently. This will make it easier for architectures to migrate to generic entry code. Suggested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/20250213130007.1418890-2-ruanjinjie@huawei.com Link: https://lore.kernel.org/all/20250624-generic-entry-split-v1-1-53d5ef4f94df@linaro.org [Linus Walleij: rebase onto v6.16-rc1] |
||
|
Dmitry Vyukov
|
a2fc422ed7 |
syscall_user_dispatch: Add PR_SYS_DISPATCH_INCLUSIVE_ON
There are two possible scenarios for syscall filtering: - having a trusted/allowed range of PCs, and intercepting everything else - or the opposite: a single untrusted/intercepted range and allowing everything else (this is relevant for any kind of sandboxing scenario, or monitoring behavior of a single library) The current API only allows the former use case due to allowed range wrap-around check. Add PR_SYS_DISPATCH_INCLUSIVE_ON that enables the second use case. Add PR_SYS_DISPATCH_EXCLUSIVE_ON alias for PR_SYS_DISPATCH_ON to make it clear how it's different from the new PR_SYS_DISPATCH_INCLUSIVE_ON. Signed-off-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/97947cc8e205ff49675826d7b0327ef2e2c66eea.1747839857.git.dvyukov@google.com |
||
|
Charlie Jenkins
|
e43b8bb56e |
entry: Inline syscall_exit_to_user_mode()
Similar to commit
|
||
|
Linus Torvalds
|
5a658afd46 |
Objtool changes for v6.15:
- The biggest change is the new option to automatically fail
the build on objtool warnings: CONFIG_OBJTOOL_WERROR.
While there are no currently known unfixed false positives
left, such an expansion in the severity of objtool warnings
inevitably creates a risk of build failures, so it's disabled by
default and depends on !COMPILE_TEST, so it shouldn't be enabled
on allyesconfig/allmodconfig builds and won't be forced on people
who just accept build-time defaults in 'make oldconfig'.
While the option is strongly recommended, only people who enable
it explicitly should see it.
(Josh Poimboeuf)
- Disable branch profiling in noinstr code with a broad
brush that includes all of arch/x86/ and kernel/sched/. (Josh Poimboeuf)
- Create backup object files on objtool errors and print exact
objtool arguments to make failure analysis easier (Josh Poimboeuf)
- Improve noreturn handling (Josh Poimboeuf)
- Improve rodata handling (Tiezhu Yang)
- Support jump tables, switch tables and goto tables on LoongArch (Tiezhu Yang)
- Misc cleanups and fixes (Josh Poimboeuf, David Engraf, Ingo Molnar)
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=iswJ
-----END PGP SIGNATURE-----
Merge tag 'objtool-core-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool updates from Ingo Molnar:
- The biggest change is the new option to automatically fail the build
on objtool warnings: CONFIG_OBJTOOL_WERROR.
While there are no currently known unfixed false positives left, such
an expansion in the severity of objtool warnings inevitably creates a
risk of build failures, so it's disabled by default and depends on
!COMPILE_TEST, so it shouldn't be enabled on
allyesconfig/allmodconfig builds and won't be forced on people who
just accept build-time defaults in 'make oldconfig'.
While the option is strongly recommended, only people who enable it
explicitly should see it.
(Josh Poimboeuf)
- Disable branch profiling in noinstr code with a broad brush that
includes all of arch/x86/ and kernel/sched/. (Josh Poimboeuf)
- Create backup object files on objtool errors and print exact objtool
arguments to make failure analysis easier (Josh Poimboeuf)
- Improve noreturn handling (Josh Poimboeuf)
- Improve rodata handling (Tiezhu Yang)
- Support jump tables, switch tables and goto tables on LoongArch
(Tiezhu Yang)
- Misc cleanups and fixes (Josh Poimboeuf, David Engraf, Ingo Molnar)
* tag 'objtool-core-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits)
tracing: Disable branch profiling in noinstr code
objtool: Use O_CREAT with explicit mode mask
objtool: Add CONFIG_OBJTOOL_WERROR
objtool: Create backup on error and print args
objtool: Change "warning:" to "error:" for --Werror
objtool: Add --Werror option
objtool: Add --output option
objtool: Upgrade "Linked object detected" warning to error
objtool: Consolidate option validation
objtool: Remove --unret dependency on --rethunk
objtool: Increase per-function WARN_FUNC() rate limit
objtool: Update documentation
objtool: Improve __noreturn annotation warning
objtool: Fix error handling inconsistencies in check()
x86/traps: Make exc_double_fault() consistently noreturn
LoongArch: Enable jump table for objtool
objtool/LoongArch: Add support for goto table
objtool/LoongArch: Add support for switch table
objtool: Handle PC relative relocation type
objtool: Handle different entry size of rodata
...
|
||
|
Josh Poimboeuf
|
2cbb20b008 |
tracing: Disable branch profiling in noinstr code
CONFIG_TRACE_BRANCH_PROFILING inserts a call to ftrace_likely_update() for each use of likely() or unlikely(). That breaks noinstr rules if the affected function is annotated as noinstr. Disable branch profiling for files with noinstr functions. In addition to some individual files, this also includes the entire arch/x86 subtree, as well as the kernel/entry, drivers/cpuidle, and drivers/idle directories, all of which are noinstr-heavy. Due to the nature of how sched binaries are built by combining multiple .c files into one, branch profiling is disabled more broadly across the sched code than would otherwise be needed. This fixes many warnings like the following: vmlinux.o: warning: objtool: do_syscall_64+0x40: call to ftrace_likely_update() leaves .noinstr.text section vmlinux.o: warning: objtool: __rdgsbase_inactive+0x33: call to ftrace_likely_update() leaves .noinstr.text section vmlinux.o: warning: objtool: handle_bug.isra.0+0x198: call to ftrace_likely_update() leaves .noinstr.text section ... Reported-by: Ingo Molnar <mingo@kernel.org> Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/fb94fc9303d48a5ed370498f54500cc4c338eb6d.1742586676.git.jpoimboe@kernel.org |
||
|
Oleg Nesterov
|
1027cd8084 |
seccomp: remove the 'sd' argument from __secure_computing()
After the previous changes 'sd' is always NULL. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Kees Cook <kees@kernel.org> Link: https://lore.kernel.org/r/20250128150313.GA15336@redhat.com Signed-off-by: Kees Cook <kees@kernel.org> |
||
|
Peter Zijlstra
|
26baa1f1c4 |
sched: Add TIF_NEED_RESCHED_LAZY infrastructure
Add the basic infrastructure to split the TIF_NEED_RESCHED bit in two. Either bit will cause a resched on return-to-user, but only TIF_NEED_RESCHED will drive IRQ preemption. No behavioural change intended. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lkml.kernel.org/r/20241007075055.219540785@infradead.org |
||
|
Valentin Schneider
|
d65d411c92 |
treewide: context_tracking: Rename CONTEXT_* into CT_STATE_*
Context tracking state related symbols currently use a mix of the CONTEXT_ (e.g. CONTEXT_KERNEL) and CT_SATE_ (e.g. CT_STATE_MASK) prefixes. Clean up the naming and make the ctx_state enum use the CT_STATE_ prefix. Suggested-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Valentin Schneider <vschneid@redhat.com> Acked-by: Frederic Weisbecker <frederic@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org> |
||
|
André Rösti
|
fb13b11d53 |
entry: Respect changes to system call number by trace_sys_enter()
When a probe is registered at the trace_sys_enter() tracepoint, and that probe changes the system call number, the old system call still gets executed. This worked correctly until commit |
||
|
Sven Schnelle
|
221a164035 |
entry: Move syscall_enter_from_user_mode() to header file
To allow inlining of syscall_enter_from_user_mode(), move it to entry-common.h. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20231218074520.1998026-4-svens@linux.ibm.com |
||
|
Sven Schnelle
|
caf4062e35 |
entry: Move enter_from_user_mode() to header file
To allow inlining of enter_from_user_mode(), move it to entry-common.h. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20231218074520.1998026-3-svens@linux.ibm.com |
||
|
Sven Schnelle
|
d680194719 |
entry: Move exit to usermode functions to header file
To allow inlining, move exit_to_user_mode() to entry-common.h. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20231218074520.1998026-2-svens@linux.ibm.com |
||
|
Mark Rutland
|
1dfe3a5a7c |
entry: Remove empty addr_limit_user_check()
Back when set_fs() was a generic API for altering the address limit,
addr_limit_user_check() was a safety measure to prevent userspace being
able to issue syscalls with an unbound limit.
With the the removal of set_fs() as a generic API, the last user of
addr_limit_user_check() was removed in commit:
|
||
|
Gregory Price
|
3f67987cdc |
ptrace: Provide set/get interface for syscall user dispatch
The syscall user dispatch configuration can only be set by the task itself, but lacks a ptrace set/get interface which makes it impossible to implement checkpoint/restore for it. Add the required ptrace requests and the get/set functions in the syscall user dispatch code to make that possible. Signed-off-by: Gregory Price <gregory.price@memverge.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/r/20230407171834.3558-4-gregory.price@memverge.com |
||
|
Gregory Price
|
463b7715e7 |
syscall_user_dispatch: Untag selector address before access_ok()
To support checkpoint/restart, ptrace must be able to set the selector of the tracee. The selector is a user pointer that may be subject to memory tagging extensions on some architectures (namely ARM MTE). access_ok() clears memory tags for tagged addresses if the current task has memory tagging enabled. This obviously fails when ptrace modifies the selector of a tracee when tracer and tracee do not have the same memory tagging enabled state. Solve this by untagging the selector address before handing it to access_ok(), like other ptrace functions which modify tracee pointers do. Obviously a tracer can set an invalid selector address for the tracee, but that's independent of tagging and a general capability of the tracer. Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Gregory Price <gregory.price@memverge.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/all/ZCWXE04nLZ4pXEtM@arm.com/ Link: https://lore.kernel.org/r/20230407171834.3558-3-gregory.price@memverge.com |
||
|
Gregory Price
|
4336068632 |
syscall_user_dispatch: Split up set_syscall_user_dispatch()
syscall user dispatch configuration is not covered by checkpoint/restore. To prepare for ptrace access to the syscall user dispatch configuration, move the inner working of set_syscall_user_dispatch() into a helper function. Make the helper function task pointer based and let set_syscall_user_dispatch() invoke it with task=current. No functional change. Signed-off-by: Gregory Price <gregory.price@memverge.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/r/20230407171834.3558-2-gregory.price@memverge.com |
||
|
Frederic Weisbecker
|
b416514054 |
entry/rcu: Check TIF_RESCHED _after_ delayed RCU wake-up
RCU sometimes needs to perform a delayed wake up for specific kthreads
handling offloaded callbacks (RCU_NOCB). These wakeups are performed
by timers and upon entry to idle (also to guest and to user on nohz_full).
However the delayed wake-up on kernel exit is actually performed after
the thread flags are fetched towards the fast path check for work to
do on exit to user. As a result, and if there is no other pending work
to do upon that kernel exit, the current task will resume to userspace
with TIF_RESCHED set and the pending wake up ignored.
Fix this with fetching the thread flags _after_ the delayed RCU-nocb
kthread wake-up.
Fixes:
|
||
|
Josh Poimboeuf
|
f87d28673b |
entry: Fix noinstr warning in __enter_from_user_mode()
__enter_from_user_mode() is triggering noinstr warnings with
CONFIG_DEBUG_PREEMPT due to its call of preempt_count_add() via
ct_state().
The preemption disable isn't needed as interrupts are already disabled.
And the context_tracking_enabled() check in ct_state() also isn't needed
as that's already being done by the CT_WARN_ON().
Just use __ct_state() instead.
Fixes the following warnings:
vmlinux.o: warning: objtool: enter_from_user_mode+0xba: call to preempt_count_add() leaves .noinstr.text section
vmlinux.o: warning: objtool: syscall_enter_from_user_mode+0xf9: call to preempt_count_add() leaves .noinstr.text section
vmlinux.o: warning: objtool: syscall_enter_from_user_mode_prepare+0xc7: call to preempt_count_add() leaves .noinstr.text section
vmlinux.o: warning: objtool: irqentry_enter_from_user_mode+0xba: call to preempt_count_add() leaves .noinstr.text section
Fixes:
|
||
|
Alexander Potapenko
|
6cae637fa2 |
entry: kmsan: introduce kmsan_unpoison_entry_regs()
struct pt_regs passed into IRQ entry code is set up by uninstrumented asm functions, therefore KMSAN may not notice the registers are initialized. kmsan_unpoison_entry_regs() unpoisons the contents of struct pt_regs, preventing potential false positives. Unlike kmsan_unpoison_memory(), it can be called under kmsan_in_runtime(), which is often the case in IRQ entry code. Link: https://lkml.kernel.org/r/20220915150417.722975-41-glider@google.com Signed-off-by: Alexander Potapenko <glider@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Eric Biggers <ebiggers@kernel.org> Cc: Eric Dumazet <edumazet@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Ilya Leoshkevich <iii@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Kees Cook <keescook@chromium.org> Cc: Marco Elver <elver@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
|
Frederic Weisbecker
|
493c182282 |
context_tracking: Take NMI eqs entrypoints over RCU
The RCU dynticks counter is going to be merged into the context tracking subsystem. Prepare with moving the NMI extended quiescent states entrypoints to context tracking. For now those are dumb redirection to existing RCU calls. Acked-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Neeraj Upadhyay <quic_neeraju@quicinc.com> Cc: Uladzislau Rezki <uladzislau.rezki@sony.com> Cc: Joel Fernandes <joel@joelfernandes.org> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Nicolas Saenz Julienne <nsaenz@kernel.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Xiongfeng Wang <wangxiongfeng2@huawei.com> Cc: Yu Liao <liaoyu15@huawei.com> Cc: Phil Auld <pauld@redhat.com> Cc: Paul Gortmaker<paul.gortmaker@windriver.com> Cc: Alex Belits <abelits@marvell.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Reviewed-by: Nicolas Saenz Julienne <nsaenzju@redhat.com> Tested-by: Nicolas Saenz Julienne <nsaenzju@redhat.com> |
||
|
Frederic Weisbecker
|
6f0e6c1598 |
context_tracking: Take IRQ eqs entrypoints over RCU
The RCU dynticks counter is going to be merged into the context tracking subsystem. Prepare with moving the IRQ extended quiescent states entrypoints to context tracking. For now those are dumb redirection to existing RCU calls. [ paulmck: Apply Stephen Rothwell feedback from -next. ] [ paulmck: Apply Nathan Chancellor feedback. ] Acked-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Neeraj Upadhyay <quic_neeraju@quicinc.com> Cc: Uladzislau Rezki <uladzislau.rezki@sony.com> Cc: Joel Fernandes <joel@joelfernandes.org> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Nicolas Saenz Julienne <nsaenz@kernel.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Xiongfeng Wang <wangxiongfeng2@huawei.com> Cc: Yu Liao <liaoyu15@huawei.com> Cc: Phil Auld <pauld@redhat.com> Cc: Paul Gortmaker<paul.gortmaker@windriver.com> Cc: Alex Belits <abelits@marvell.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Reviewed-by: Nicolas Saenz Julienne <nsaenzju@redhat.com> Tested-by: Nicolas Saenz Julienne <nsaenzju@redhat.com> |
||
|
Linus Torvalds
|
34f4335c16 |
* Fix syzkaller NULL pointer dereference
* Fix TDP MMU performance issue with disabling dirty logging * Fix 5.14 regression with SVM TSC scaling * Fix indefinite stall on applying live patches * Fix unstable selftest * Fix memory leak from wrong copy-and-paste * Fix missed PV TLB flush when racing with emulation -----BEGIN PGP SIGNATURE----- iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmKglysUHHBib256aW5p QHJlZGhhdC5jb20ACgkQv/vSX3jHroOJDAgArpPcAnJbeT2VQTQcp94e4tp9k1Sf gmUewajco4zFVB/sldE0fIporETkaX+FYYPiaNDdNgJ2lUw/HUJBN7KoFEYTZ37N Xx/qXiIXQYFw1bmxTnacLzIQtD3luMCzOs/6/Q7CAFZIBpUtUEjkMlQOBuxoKeG0 B0iLCTJSw0taWcN170aN8G6T+5+bdR3AJW1k2wkgfESfYF9NfJoTUHQj9WTMzM2R aBRuXvUI/rWKvQY3DfoRmgg9Ig/SirSC+abbKIs4H08vZIEUlPk3WOZSKpsN/Wzh 3XDnVRxgnaRLx6NI/ouI2UYJCmjPKbNcueGCf5IfUcHvngHjAEG/xxe4Qw== =zQ9u -----END PGP SIGNATURE----- Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm Pull KVM fixes from Paolo Bonzini: - syzkaller NULL pointer dereference - TDP MMU performance issue with disabling dirty logging - 5.14 regression with SVM TSC scaling - indefinite stall on applying live patches - unstable selftest - memory leak from wrong copy-and-paste - missed PV TLB flush when racing with emulation * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: x86: do not report a vCPU as preempted outside instruction boundaries KVM: x86: do not set st->preempted when going back to user space KVM: SVM: fix tsc scaling cache logic KVM: selftests: Make hyperv_clock selftest more stable KVM: x86/MMU: Zap non-leaf SPTEs when disabling dirty logging x86: drop bogus "cc" clobber from __try_cmpxchg_user_asm() KVM: x86/mmu: Check every prev_roots in __kvm_mmu_free_obsolete_roots() entry/kvm: Exit to user mode when TIF_NOTIFY_SIGNAL is set KVM: Don't null dereference ops->destroy |
||
|
Seth Forshee
|
3e684903a8 |
entry/kvm: Exit to user mode when TIF_NOTIFY_SIGNAL is set
A livepatch transition may stall indefinitely when a kvm vCPU is heavily loaded. To the host, the vCPU task is a user thread which is spending a very long time in the ioctl(KVM_RUN) syscall. During livepatch transition, set_notify_signal() will be called on such tasks to interrupt the syscall so that the task can be transitioned. This interrupts guest execution, but when xfer_to_guest_mode_work() sees that TIF_NOTIFY_SIGNAL is set but not TIF_SIGPENDING it concludes that an exit to user mode is unnecessary, and guest execution is resumed without transitioning the task for the livepatch. This handling of TIF_NOTIFY_SIGNAL is incorrect, as set_notify_signal() is expected to break tasks out of interruptible kernel loops and cause them to return to userspace. Change xfer_to_guest_mode_work() to handle TIF_NOTIFY_SIGNAL the same as TIF_SIGPENDING, signaling to the vCPU run loop that an exit to userpsace is needed. Any pending task_work will be run when get_signal() is called from exit_to_user_mode_loop(), so there is no longer any need to run task work from xfer_to_guest_mode_work(). Suggested-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Petr Mladek <pmladek@suse.com> Signed-off-by: Seth Forshee <sforshee@digitalocean.com> Message-Id: <20220504180840.2907296-1-sforshee@digitalocean.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Linus Torvalds
|
2319be1356 |
Locking changes in this cycle were:
- rwsem cleanups & optimizations/fixes:
- Conditionally wake waiters in reader/writer slowpaths
- Always try to wake waiters in out_nolock path
- Add try_cmpxchg64() implementation, with arch optimizations - and use it to
micro-optimize sched_clock_{local,remote}()
- Various force-inlining fixes to address objdump instrumentation-check warnings
- Add lock contention tracepoints:
lock:contention_begin
lock:contention_end
- Misc smaller fixes & cleanups
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----
iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmKLsrERHG1pbmdvQGtl
cm5lbC5vcmcACgkQEnMQ0APhK1js3g//cPR9PYlvZv87T2hI8VWKfNzapgSmwCsH
1P+nk27Pef+jfxHr/N7YScvSD06+z2wIroLE3npPNETmNd1X8obBDThmeD4VI899
J6h4sE0cFOpTG/mHeECFxqnDuzhdHiRHWS52RxOwTjZTpdbeKWZYueC0Mvqn+tIp
UM2D2yTseIHs67ikxYtayU/iJgSZ+PYrMPv9nSVUjIFILmg7gMIz38OZYQzR84++
auL3m8sAq/i2pjzDBbXMpfYeu177/tPHpPJr2rOErLEXWqK2K6op8+CbX4z3yv3z
EBBhGiUNqDmFaFuIgg7Mx94SvPh8MBGexUnT0XA2aXPwyP9oAaenCk2CZ1j9u15m
/Xp1A4KNvg1WY8jHu5ZM4VIEXQ7d6Gwtbej7IeovUxBD6y7Trb3+rxb7PVdZX941
uVGjss1Lgk70wUQqBqBPmBm08O6NUF3vekHlona5CZTQgEF84zD7+7D++QPaAZo7
kiuNUptdgfq6X0xqgP88GX1KU85gJYoF5Q13vb7lAcv19QhRG5JBJeWMYiXEmg12
Ktl97Sru0zCpCY1NCvwsBll09SLVO9kX3Lq+QFD8bFMZ0obsGIBotHq1qH6U7cH8
RY6esVBF/1/+qdrxOKs8qowlJ4EUp/3bX0R/MKYHJJbulj/aaE916HvMsoN/QR4Y
oW7GcxMQGLE=
=gaS5
-----END PGP SIGNATURE-----
Merge tag 'locking-core-2022-05-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
- rwsem cleanups & optimizations/fixes:
- Conditionally wake waiters in reader/writer slowpaths
- Always try to wake waiters in out_nolock path
- Add try_cmpxchg64() implementation, with arch optimizations - and use
it to micro-optimize sched_clock_{local,remote}()
- Various force-inlining fixes to address objdump instrumentation-check
warnings
- Add lock contention tracepoints:
lock:contention_begin
lock:contention_end
- Misc smaller fixes & cleanups
* tag 'locking-core-2022-05-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/clock: Use try_cmpxchg64 in sched_clock_{local,remote}
locking/atomic/x86: Introduce arch_try_cmpxchg64
locking/atomic: Add generic try_cmpxchg64 support
futex: Remove a PREEMPT_RT_FULL reference.
locking/qrwlock: Change "queue rwlock" to "queued rwlock"
lockdep: Delete local_irq_enable_in_hardirq()
locking/mutex: Make contention tracepoints more consistent wrt adaptive spinning
locking: Apply contention tracepoints in the slow path
locking: Add lock contention tracepoints
locking/rwsem: Always try to wake waiters in out_nolock path
locking/rwsem: Conditionally wake waiters in reader/writer slowpaths
locking/rwsem: No need to check for handoff bit if wait queue empty
lockdep: Fix -Wunused-parameter for _THIS_IP_
x86/mm: Force-inline __phys_addr_nodebug()
x86/kvm/svm: Force-inline GHCB accessors
task_stack, x86/cea: Force-inline stack helpers
|
||
|
Sven Schnelle
|
6d97af487d |
entry: Rename arch_check_user_regs() to arch_enter_from_user_mode()
arch_check_user_regs() is used at the moment to verify that struct pt_regs contains valid values when entering the kernel from userspace. s390 needs a place in the generic entry code to modify a cpu data structure when switching from userspace to kernel mode. As arch_check_user_regs() is exactly this, rename it to arch_enter_from_user_mode(). When entering the kernel from userspace, arch_check_user_regs() is used to verify that struct pt_regs contains valid values. Note that the NMI codepath doesn't call this function. s390 needs a place in the generic entry code to modify a cpu data structure when switching from userspace to kernel mode. As arch_check_user_regs() is exactly this, rename it to arch_enter_from_user_mode(). Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andy Lutomirski <luto@kernel.org> Link: https://lore.kernel.org/r/20220504062351.2954280-2-tmricht@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com> |
||
|
Nick Desaulniers
|
8b023accc8 |
lockdep: Fix -Wunused-parameter for _THIS_IP_
While looking into a bug related to the compiler's handling of addresses of labels, I noticed some uses of _THIS_IP_ seemed unused in lockdep. Drive by cleanup. -Wunused-parameter: kernel/locking/lockdep.c:1383:22: warning: unused parameter 'ip' kernel/locking/lockdep.c:4246:48: warning: unused parameter 'ip' kernel/locking/lockdep.c:4844:19: warning: unused parameter 'ip' Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Waiman Long <longman@redhat.com> Link: https://lore.kernel.org/r/20220314221909.2027027-1-ndesaulniers@google.com |
||
|
Sven Schnelle
|
0a70045ed8 |
entry: Fix compile error in dynamic_irqentry_exit_cond_resched()
kernel/entry/common.c: In function ‘dynamic_irqentry_exit_cond_resched’:
kernel/entry/common.c:409:14: error: implicit declaration of function ‘static_key_unlikely’; did you mean ‘static_key_enable’? [-Werror=implicit-function-declaration]
409 | if (!static_key_unlikely(&sk_dynamic_irqentry_exit_cond_resched))
| ^~~~~~~~~~~~~~~~~~~
| static_key_enable
static_key_unlikely() should be static_branch_unlikely().
Fixes:
|
||
|
Thomas Gleixner
|
7dd5ad2d3e |
Revert "signal, x86: Delay calling signals in atomic on RT enabled kernels"
Revert commit
|
||
|
Linus Torvalds
|
1930a6e739 |
ptrace: Cleanups for v5.18
This set of changes removes tracehook.h, moves modification of all of
the ptrace fields inside of siglock to remove races, adds a missing
permission check to ptrace.c
The removal of tracehook.h is quite significant as it has been a major
source of confusion in recent years. Much of that confusion was
around task_work and TIF_NOTIFY_SIGNAL (which I have now decoupled
making the semantics clearer).
For people who don't know tracehook.h is a vestiage of an attempt to
implement uprobes like functionality that was never fully merged, and
was later superseeded by uprobes when uprobes was merged. For many
years now we have been removing what tracehook functionaly a little
bit at a time. To the point where now anything left in tracehook.h is
some weird strange thing that is difficult to understand.
Eric W. Biederman (15):
ptrace: Move ptrace_report_syscall into ptrace.h
ptrace/arm: Rename tracehook_report_syscall report_syscall
ptrace: Create ptrace_report_syscall_{entry,exit} in ptrace.h
ptrace: Remove arch_syscall_{enter,exit}_tracehook
ptrace: Remove tracehook_signal_handler
task_work: Remove unnecessary include from posix_timers.h
task_work: Introduce task_work_pending
task_work: Call tracehook_notify_signal from get_signal on all architectures
task_work: Decouple TIF_NOTIFY_SIGNAL and task_work
signal: Move set_notify_signal and clear_notify_signal into sched/signal.h
resume_user_mode: Remove #ifdef TIF_NOTIFY_RESUME in set_notify_resume
resume_user_mode: Move to resume_user_mode.h
tracehook: Remove tracehook.h
ptrace: Move setting/clearing ptrace_message into ptrace_stop
ptrace: Return the signal to continue with from ptrace_stop
Jann Horn (1):
ptrace: Check PTRACE_O_SUSPEND_SECCOMP permission on PTRACE_SEIZE
Yang Li (1):
ptrace: Remove duplicated include in ptrace.c
MAINTAINERS | 1 -
arch/Kconfig | 5 +-
arch/alpha/kernel/ptrace.c | 5 +-
arch/alpha/kernel/signal.c | 4 +-
arch/arc/kernel/ptrace.c | 5 +-
arch/arc/kernel/signal.c | 4 +-
arch/arm/kernel/ptrace.c | 12 +-
arch/arm/kernel/signal.c | 4 +-
arch/arm64/kernel/ptrace.c | 14 +--
arch/arm64/kernel/signal.c | 4 +-
arch/csky/kernel/ptrace.c | 5 +-
arch/csky/kernel/signal.c | 4 +-
arch/h8300/kernel/ptrace.c | 5 +-
arch/h8300/kernel/signal.c | 4 +-
arch/hexagon/kernel/process.c | 4 +-
arch/hexagon/kernel/signal.c | 1 -
arch/hexagon/kernel/traps.c | 6 +-
arch/ia64/kernel/process.c | 4 +-
arch/ia64/kernel/ptrace.c | 6 +-
arch/ia64/kernel/signal.c | 1 -
arch/m68k/kernel/ptrace.c | 5 +-
arch/m68k/kernel/signal.c | 4 +-
arch/microblaze/kernel/ptrace.c | 5 +-
arch/microblaze/kernel/signal.c | 4 +-
arch/mips/kernel/ptrace.c | 5 +-
arch/mips/kernel/signal.c | 4 +-
arch/nds32/include/asm/syscall.h | 2 +-
arch/nds32/kernel/ptrace.c | 5 +-
arch/nds32/kernel/signal.c | 4 +-
arch/nios2/kernel/ptrace.c | 5 +-
arch/nios2/kernel/signal.c | 4 +-
arch/openrisc/kernel/ptrace.c | 5 +-
arch/openrisc/kernel/signal.c | 4 +-
arch/parisc/kernel/ptrace.c | 7 +-
arch/parisc/kernel/signal.c | 4 +-
arch/powerpc/kernel/ptrace/ptrace.c | 8 +-
arch/powerpc/kernel/signal.c | 4 +-
arch/riscv/kernel/ptrace.c | 5 +-
arch/riscv/kernel/signal.c | 4 +-
arch/s390/include/asm/entry-common.h | 1 -
arch/s390/kernel/ptrace.c | 1 -
arch/s390/kernel/signal.c | 5 +-
arch/sh/kernel/ptrace_32.c | 5 +-
arch/sh/kernel/signal_32.c | 4 +-
arch/sparc/kernel/ptrace_32.c | 5 +-
arch/sparc/kernel/ptrace_64.c | 5 +-
arch/sparc/kernel/signal32.c | 1 -
arch/sparc/kernel/signal_32.c | 4 +-
arch/sparc/kernel/signal_64.c | 4 +-
arch/um/kernel/process.c | 4 +-
arch/um/kernel/ptrace.c | 5 +-
arch/x86/kernel/ptrace.c | 1 -
arch/x86/kernel/signal.c | 5 +-
arch/x86/mm/tlb.c | 1 +
arch/xtensa/kernel/ptrace.c | 5 +-
arch/xtensa/kernel/signal.c | 4 +-
block/blk-cgroup.c | 2 +-
fs/coredump.c | 1 -
fs/exec.c | 1 -
fs/io-wq.c | 6 +-
fs/io_uring.c | 11 +-
fs/proc/array.c | 1 -
fs/proc/base.c | 1 -
include/asm-generic/syscall.h | 2 +-
include/linux/entry-common.h | 47 +-------
include/linux/entry-kvm.h | 2 +-
include/linux/posix-timers.h | 1 -
include/linux/ptrace.h | 81 ++++++++++++-
include/linux/resume_user_mode.h | 64 ++++++++++
include/linux/sched/signal.h | 17 +++
include/linux/task_work.h | 5 +
include/linux/tracehook.h | 226 -----------------------------------
include/uapi/linux/ptrace.h | 2 +-
kernel/entry/common.c | 19 +--
kernel/entry/kvm.c | 9 +-
kernel/exit.c | 3 +-
kernel/livepatch/transition.c | 1 -
kernel/ptrace.c | 47 +++++---
kernel/seccomp.c | 1 -
kernel/signal.c | 62 +++++-----
kernel/task_work.c | 4 +-
kernel/time/posix-cpu-timers.c | 1 +
mm/memcontrol.c | 2 +-
security/apparmor/domain.c | 1 -
security/selinux/hooks.c | 1 -
85 files changed, 372 insertions(+), 495 deletions(-)
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
-----BEGIN PGP SIGNATURE-----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=uEro
-----END PGP SIGNATURE-----
Merge tag 'ptrace-cleanups-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull ptrace cleanups from Eric Biederman:
"This set of changes removes tracehook.h, moves modification of all of
the ptrace fields inside of siglock to remove races, adds a missing
permission check to ptrace.c
The removal of tracehook.h is quite significant as it has been a major
source of confusion in recent years. Much of that confusion was around
task_work and TIF_NOTIFY_SIGNAL (which I have now decoupled making the
semantics clearer).
For people who don't know tracehook.h is a vestiage of an attempt to
implement uprobes like functionality that was never fully merged, and
was later superseeded by uprobes when uprobes was merged. For many
years now we have been removing what tracehook functionaly a little
bit at a time. To the point where anything left in tracehook.h was
some weird strange thing that was difficult to understand"
* tag 'ptrace-cleanups-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
ptrace: Remove duplicated include in ptrace.c
ptrace: Check PTRACE_O_SUSPEND_SECCOMP permission on PTRACE_SEIZE
ptrace: Return the signal to continue with from ptrace_stop
ptrace: Move setting/clearing ptrace_message into ptrace_stop
tracehook: Remove tracehook.h
resume_user_mode: Move to resume_user_mode.h
resume_user_mode: Remove #ifdef TIF_NOTIFY_RESUME in set_notify_resume
signal: Move set_notify_signal and clear_notify_signal into sched/signal.h
task_work: Decouple TIF_NOTIFY_SIGNAL and task_work
task_work: Call tracehook_notify_signal from get_signal on all architectures
task_work: Introduce task_work_pending
task_work: Remove unnecessary include from posix_timers.h
ptrace: Remove tracehook_signal_handler
ptrace: Remove arch_syscall_{enter,exit}_tracehook
ptrace: Create ptrace_report_syscall_{entry,exit} in ptrace.h
ptrace/arm: Rename tracehook_report_syscall report_syscall
ptrace: Move ptrace_report_syscall into ptrace.h
|
||
|
Linus Torvalds
|
3fe2f7446f |
Changes in this cycle were:
- Cleanups for SCHED_DEADLINE
- Tracing updates/fixes
- CPU Accounting fixes
- First wave of changes to optimize the overhead of the scheduler build,
from the fast-headers tree - including placeholder *_api.h headers for
later header split-ups.
- Preempt-dynamic using static_branch() for ARM64
- Isolation housekeeping mask rework; preperatory for further changes
- NUMA-balancing: deal with CPU-less nodes
- NUMA-balancing: tune systems that have multiple LLC cache domains per node (eg. AMD)
- Updates to RSEQ UAPI in preparation for glibc usage
- Lots of RSEQ/selftests, for same
- Add Suren as PSI co-maintainer
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=Z8uT
-----END PGP SIGNATURE-----
Merge tag 'sched-core-2022-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
- Cleanups for SCHED_DEADLINE
- Tracing updates/fixes
- CPU Accounting fixes
- First wave of changes to optimize the overhead of the scheduler
build, from the fast-headers tree - including placeholder *_api.h
headers for later header split-ups.
- Preempt-dynamic using static_branch() for ARM64
- Isolation housekeeping mask rework; preperatory for further changes
- NUMA-balancing: deal with CPU-less nodes
- NUMA-balancing: tune systems that have multiple LLC cache domains per
node (eg. AMD)
- Updates to RSEQ UAPI in preparation for glibc usage
- Lots of RSEQ/selftests, for same
- Add Suren as PSI co-maintainer
* tag 'sched-core-2022-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (81 commits)
sched/headers: ARM needs asm/paravirt_api_clock.h too
sched/numa: Fix boot crash on arm64 systems
headers/prep: Fix header to build standalone: <linux/psi.h>
sched/headers: Only include <linux/entry-common.h> when CONFIG_GENERIC_ENTRY=y
cgroup: Fix suspicious rcu_dereference_check() usage warning
sched/preempt: Tell about PREEMPT_DYNAMIC on kernel headers
sched/topology: Remove redundant variable and fix incorrect type in build_sched_domains
sched/deadline,rt: Remove unused parameter from pick_next_[rt|dl]_entity()
sched/deadline,rt: Remove unused functions for !CONFIG_SMP
sched/deadline: Use __node_2_[pdl|dle]() and rb_first_cached() consistently
sched/deadline: Merge dl_task_can_attach() and dl_cpu_busy()
sched/deadline: Move bandwidth mgmt and reclaim functions into sched class source file
sched/deadline: Remove unused def_dl_bandwidth
sched/tracing: Report TASK_RTLOCK_WAIT tasks as TASK_UNINTERRUPTIBLE
sched/tracing: Don't re-read p->state when emitting sched_switch event
sched/rt: Plug rt_mutex_setprio() vs push_rt_task() race
sched/cpuacct: Remove redundant RCU read lock
sched/cpuacct: Optimize away RCU read lock
sched/cpuacct: Fix charge percpu cpuusage
sched/headers: Reorganize, clean up and optimize kernel/sched/sched.h dependencies
...
|
||
|
Eric W. Biederman
|
03248addad |
resume_user_mode: Move to resume_user_mode.h
Move set_notify_resume and tracehook_notify_resume into resume_user_mode.h. While doing that rename tracehook_notify_resume to resume_user_mode_work. Update all of the places that included tracehook.h for these functions to include resume_user_mode.h instead. Update all of the callers of tracehook_notify_resume to call resume_user_mode_work. Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lkml.kernel.org/r/20220309162454.123006-12-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> |
||
|
Eric W. Biederman
|
7c5d8fa6fb |
task_work: Decouple TIF_NOTIFY_SIGNAL and task_work
There are a small handful of reasons besides pending signals that the kernel might want to break out of interruptible sleeps. The flag TIF_NOTIFY_SIGNAL and the helpers that set and clear TIF_NOTIFY_SIGNAL provide that the infrastructure for breaking out of interruptible sleeps and entering the return to user space slow path for those cases. Expand tracehook_notify_signal inline in it's callers and remove it, which makes clear that TIF_NOTIFY_SIGNAL and task_work are separate concepts. Update the comment on set_notify_signal to more accurately describe it's purpose. Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lkml.kernel.org/r/20220309162454.123006-9-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> |
||
|
Eric W. Biederman
|
8ba62d3794 |
task_work: Call tracehook_notify_signal from get_signal on all architectures
Always handle TIF_NOTIFY_SIGNAL in get_signal. With commit
|
||
|
Eric W. Biederman
|
0cfcb2b9ef |
ptrace: Remove arch_syscall_{enter,exit}_tracehook
These functions are alwasy one-to-one wrappers around ptrace_report_syscall_entry and ptrace_report_syscall_exit. So directly call the functions they are wrapping instead. Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lkml.kernel.org/r/20220309162454.123006-4-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> |
||
|
Eric W. Biederman
|
153474ba1a |
ptrace: Create ptrace_report_syscall_{entry,exit} in ptrace.h
Rename tracehook_report_syscall_{entry,exit} to
ptrace_report_syscall_{entry,exit} and place them in ptrace.h
There is no longer any generic tracehook infractructure so make
these ptrace specific functions ptrace specific.
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20220309162454.123006-3-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
||
|
Oleg Nesterov
|
bf9ad37dc8 |
signal, x86: Delay calling signals in atomic on RT enabled kernels
On x86_64 we must disable preemption before we enable interrupts for stack faults, int3 and debugging, because the current task is using a per CPU debug stack defined by the IST. If we schedule out, another task can come in and use the same stack and cause the stack to be corrupted and crash the kernel on return. When CONFIG_PREEMPT_RT is enabled, spinlock_t locks become sleeping, and one of these is the spin lock used in signal handling. Some of the debug code (int3) causes do_trap() to send a signal. This function calls a spinlock_t lock that has been converted to a sleeping lock. If this happens, the above issues with the corrupted stack is possible. Instead of calling the signal right away, for PREEMPT_RT and x86, the signal information is stored on the stacks task_struct and TIF_NOTIFY_RESUME is set. Then on exit of the trap, the signal resume code will send the signal when preemption is enabled. [ rostedt: Switched from #ifdef CONFIG_PREEMPT_RT to ARCH_RT_DELAYS_SIGNAL_SEND and added comments to the code. ] [bigeasy: Add on 32bit as per Yang Shi, minor rewording. ] [ tglx: Use a config option ] Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/Ygq5aBB/qMQw6aP5@linutronix.de |
||
|
Mark Rutland
|
99cf983cc8 |
sched/preempt: Add PREEMPT_DYNAMIC using static keys
Where an architecture selects HAVE_STATIC_CALL but not HAVE_STATIC_CALL_INLINE, each static call has an out-of-line trampoline which will either branch to a callee or return to the caller. On such architectures, a number of constraints can conspire to make those trampolines more complicated and potentially less useful than we'd like. For example: * Hardware and software control flow integrity schemes can require the addition of "landing pad" instructions (e.g. `BTI` for arm64), which will also be present at the "real" callee. * Limited branch ranges can require that trampolines generate or load an address into a register and perform an indirect branch (or at least have a slow path that does so). This loses some of the benefits of having a direct branch. * Interaction with SW CFI schemes can be complicated and fragile, e.g. requiring that we can recognise idiomatic codegen and remove indirections understand, at least until clang proves more helpful mechanisms for dealing with this. For PREEMPT_DYNAMIC, we don't need the full power of static calls, as we really only need to enable/disable specific preemption functions. We can achieve the same effect without a number of the pain points above by using static keys to fold early returns into the preemption functions themselves rather than in an out-of-line trampoline, effectively inlining the trampoline into the start of the function. For arm64, this results in good code generation. For example, the dynamic_cond_resched() wrapper looks as follows when enabled. When disabled, the first `B` is replaced with a `NOP`, resulting in an early return. | <dynamic_cond_resched>: | bti c | b <dynamic_cond_resched+0x10> // or `nop` | mov w0, #0x0 | ret | mrs x0, sp_el0 | ldr x0, [x0, #8] | cbnz x0, <dynamic_cond_resched+0x8> | paciasp | stp x29, x30, [sp, #-16]! | mov x29, sp | bl <preempt_schedule_common> | mov w0, #0x1 | ldp x29, x30, [sp], #16 | autiasp | ret ... compared to the regular form of the function: | <__cond_resched>: | bti c | mrs x0, sp_el0 | ldr x1, [x0, #8] | cbz x1, <__cond_resched+0x18> | mov w0, #0x0 | ret | paciasp | stp x29, x30, [sp, #-16]! | mov x29, sp | bl <preempt_schedule_common> | mov w0, #0x1 | ldp x29, x30, [sp], #16 | autiasp | ret Any architecture which implements static keys should be able to use this to implement PREEMPT_DYNAMIC with similar cost to non-inlined static calls. Since this is likely to have greater overhead than (inlined) static calls, PREEMPT_DYNAMIC is only defaulted to enabled when HAVE_PREEMPT_DYNAMIC_CALL is selected. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20220214165216.2231574-6-mark.rutland@arm.com |
||
|
Mark Rutland
|
4624a14f4d |
sched/preempt: Simplify irqentry_exit_cond_resched() callers
Currently callers of irqentry_exit_cond_resched() need to be aware of whether the function should be indirected via a static call, leading to ugly ifdeffery in callers. Save them the hassle with a static inline wrapper that does the right thing. The raw_irqentry_exit_cond_resched() will also be useful in subsequent patches which will add conditional wrappers for preemption functions. Note: in arch/x86/entry/common.c, xen_pv_evtchn_do_upcall() always calls irqentry_exit_cond_resched() directly, even when PREEMPT_DYNAMIC is in use. I believe this is a latent bug (which this patch corrects), but I'm not entirely certain this wasn't deliberate. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20220214165216.2231574-4-mark.rutland@arm.com |
||
|
Mark Rutland
|
6ce895128b |
entry: Snapshot thread flags
Some thread flags can be set remotely, and so even when IRQs are disabled, the flags can change under our feet. Generally this is unlikely to cause a problem in practice, but it is somewhat unsound, and KCSAN will legitimately warn that there is a data race. To avoid such issues, a snapshot of the flags has to be taken prior to using them. Some places already use READ_ONCE() for that, others do not. Convert them all to the new flag accessor helpers. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Paul E. McKenney <paulmck@kernel.org> Link: https://lore.kernel.org/r/20211129130653.2037928-3-mark.rutland@arm.com |
||
|
Eric W. Biederman
|
fcb116bc43 |
signal: Replace force_fatal_sig with force_exit_sig when in doubt
Recently to prevent issues with SECCOMP_RET_KILL and similar signals being changed before they are delivered SA_IMMUTABLE was added. Unfortunately this broke debuggers[1][2] which reasonably expect to be able to trap synchronous SIGTRAP and SIGSEGV even when the target process is not configured to handle those signals. Add force_exit_sig and use it instead of force_fatal_sig where historically the code has directly called do_exit. This has the implementation benefits of going through the signal exit path (including generating core dumps) without the danger of allowing userspace to ignore or change these signals. This avoids userspace regressions as older kernels exited with do_exit which debuggers also can not intercept. In the future is should be possible to improve the quality of implementation of the kernel by changing some of these force_exit_sig calls to force_fatal_sig. That can be done where it matters on a case-by-case basis with careful analysis. Reported-by: Kyle Huey <me@kylehuey.com> Reported-by: kernel test robot <oliver.sang@intel.com> [1] https://lkml.kernel.org/r/CAP045AoMY4xf8aC_4QU_-j7obuEPYgTcnQQP3Yxk=2X90jtpjw@mail.gmail.com [2] https://lkml.kernel.org/r/20211117150258.GB5403@xsang-OptiPlex-9020 Fixes: |
||
|
Linus Torvalds
|
5147da902e |
Merge branch 'exit-cleanups-for-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull exit cleanups from Eric Biederman: "While looking at some issues related to the exit path in the kernel I found several instances where the code is not using the existing abstractions properly. This set of changes introduces force_fatal_sig a way of sending a signal and not allowing it to be caught, and corrects the misuse of the existing abstractions that I found. A lot of the misuse of the existing abstractions are silly things such as doing something after calling a no return function, rolling BUG by hand, doing more work than necessary to terminate a kernel thread, or calling do_exit(SIGKILL) instead of calling force_sig(SIGKILL). In the review a deficiency in force_fatal_sig and force_sig_seccomp where ptrace or sigaction could prevent the delivery of the signal was found. I have added a change that adds SA_IMMUTABLE to change that makes it impossible to interrupt the delivery of those signals, and allows backporting to fix force_sig_seccomp And Arnd found an issue where a function passed to kthread_run had the wrong prototype, and after my cleanup was failing to build." * 'exit-cleanups-for-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (23 commits) soc: ti: fix wkup_m3_rproc_boot_thread return type signal: Add SA_IMMUTABLE to ensure forced siganls do not get changed signal: Replace force_sigsegv(SIGSEGV) with force_fatal_sig(SIGSEGV) exit/r8188eu: Replace the macro thread_exit with a simple return 0 exit/rtl8712: Replace the macro thread_exit with a simple return 0 exit/rtl8723bs: Replace the macro thread_exit with a simple return 0 signal/x86: In emulate_vsyscall force a signal instead of calling do_exit signal/sparc32: In setup_rt_frame and setup_fram use force_fatal_sig signal/sparc32: Exit with a fatal signal when try_to_clear_window_buffer fails exit/syscall_user_dispatch: Send ordinary signals on failure signal: Implement force_fatal_sig exit/kthread: Have kernel threads return instead of calling do_exit signal/s390: Use force_sigsegv in default_trap_handler signal/vm86_32: Properly send SIGSEGV when the vm86 state cannot be saved. signal/vm86_32: Replace open coded BUG_ON with an actual BUG_ON signal/sparc: In setup_tsb_params convert open coded BUG into BUG signal/powerpc: On swapcontext failure force SIGSEGV signal/sh: Use force_sig(SIGKILL) instead of do_group_exit(SIGKILL) signal/mips: Update (_save|_restore)_fp_context to fail with -EFAULT signal/sparc32: Remove unreachable do_exit in do_sparc_fault ... |
||
|
Eric W. Biederman
|
941edc5bf1 |
exit/syscall_user_dispatch: Send ordinary signals on failure
Use force_fatal_sig instead of calling do_exit directly. This ensures the ordinary signal handling path gets invoked, core dumps as appropriate get created, and for multi-threaded processes all of the threads are terminated not just a single thread. When asked Gabriel Krisman Bertazi <krisman@collabora.com> said [1]: > ebiederm@xmission.com (Eric W. Biederman) asked: > > > Why does do_syscal_user_dispatch call do_exit(SIGSEGV) and > > do_exit(SIGSYS) instead of force_sig(SIGSEGV) and force_sig(SIGSYS)? > > > > Looking at the code these cases are not expected to happen, so I would > > be surprised if userspace depends on any particular behaviour on the > > failure path so I think we can change this. > > Hi Eric, > > There is not really a good reason, and the use case that originated the > feature doesn't rely on it. > > Unless I'm missing yet another problem and others correct me, I think > it makes sense to change it as you described. > > > Is using do_exit in this way something you copied from seccomp? > > I'm not sure, its been a while, but I think it might be just that. The > first prototype of SUD was implemented as a seccomp mode. If at some point it becomes interesting we could relax "force_fatal_sig(SIGSEGV)" to instead say "force_sig_fault(SIGSEGV, SEGV_MAPERR, sd->selector)". I avoid doing that in this patch to avoid making it possible to catch currently uncatchable signals. Cc: Gabriel Krisman Bertazi <krisman@collabora.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andy Lutomirski <luto@kernel.org> [1] https://lkml.kernel.org/r/87mtr6gdvi.fsf@collabora.com Link: https://lkml.kernel.org/r/20211020174406.17889-14-ebiederm@xmission.com Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> |
||
|
Sean Christopherson
|
a68de80f61 |
entry: rseq: Call rseq_handle_notify_resume() in tracehook_notify_resume()
Invoke rseq_handle_notify_resume() from tracehook_notify_resume() now
that the two function are always called back-to-back by architectures
that have rseq. The rseq helper is stubbed out for architectures that
don't support rseq, i.e. this is a nop across the board.
Note, tracehook_notify_resume() is horribly named and arguably does not
belong in tracehook.h as literally every line of code in it has nothing
to do with tracing. But, that's been true since commit
|
||
|
Sean Christopherson
|
8646e53633 |
KVM: rseq: Update rseq when processing NOTIFY_RESUME on xfer to KVM guest
Invoke rseq's NOTIFY_RESUME handler when processing the flag prior to
transferring to a KVM guest, which is roughly equivalent to an exit to
userspace and processes many of the same pending actions. While the task
cannot be in an rseq critical section as the KVM path is reachable only
by via ioctl(KVM_RUN), the side effects that apply to rseq outside of a
critical section still apply, e.g. the current CPU needs to be updated if
the task is migrated.
Clearing TIF_NOTIFY_RESUME without informing rseq can lead to segfaults
and other badness in userspace VMMs that use rseq in combination with KVM,
e.g. due to the CPU ID being stale after task migration.
Fixes:
|
||
|
Frederic Weisbecker
|
f268c3737e |
tick/nohz: Only check for RCU deferred wakeup on user/guest entry when needed
Checking for and processing RCU-nocb deferred wakeup upon user/guest entry is only relevant when nohz_full runs on the local CPU, otherwise the periodic tick should take care of it. Make sure we don't needlessly pollute these fast-paths as a -3% performance regression on a will-it-scale.per_process_ops has been reported so far. Fixes: |
||
|
Linus Torvalds
|
3b671bf4a7 |
A trivial cleanup of typo fixes.
-----BEGIN PGP SIGNATURE----- iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmCGgSATHHRnbHhAbGlu dXRyb25peC5kZQAKCRCmGPVMDXSYoTdtD/wPWKg5olDLUr3S9Oh15dPj2zzrZHl8 opJkN/0LpZvTYJmAtVrV1SCywbQYhpsLEB+khBZj0OY/A9gDRGM2uBxxL3oyvyOU hRjJkimJuNF3ErDAIFnW3rmgYPIgRnUAnS1hflUpeROHeL5CfR/nPqQgT6I79fmZ c23kbGOdz7lw5vUNPiSvpU52UT4HfTfDs5NXB3B4A7Lc2292o3xCw20/LZGsICRy 6CybMM9Lp7yKdosPZxyjjS9Fu2U2/HptmQ0ueNC4/GYKxq+zM3JDNHECZ4IXVSlu +KPgqIfrhec0fwcyWXdEPwDLvgg4XPipxr5mLi9qa45MFxXhtzeKdSD2ktUFU5QH G10VWfslDt1VBavKR4u4lz/1L0iiRW3EyuMnbuZNCvbObfNY/jKs+3Kn4OcZIYfL DurPMvBZo9BiS3+rIROEETJvzvf84sstDU2c4dZzQMKxtSs1DvVDpyypSqzBkBcr n2nWRNsAVhSz0avJ3ZP8yphy/8TFWUY9H1sLQC68ih3frn5sgKN7Ng2cWGCVzL5P 2geUmbEybdUO9x8mz6ui78kDgwrapyHZlXOQvbaSmlEDA00tEQM0XRFC+B29OwkX P37SQjlkvnH5hYxU2x+v4tCrZvrefYuv30E0RbdV5g0WPXAYUL7OH7hK+UzZkKGh iZEVlJ2vEUw/lQ== =m4pW -----END PGP SIGNATURE----- Merge tag 'core-entry-2021-04-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core entry updates from Thomas Gleixner: "A trivial cleanup of typo fixes" * tag 'core-entry-2021-04-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: entry: Fix typos in comments |
||
|
Zhouyi Zhou
|
0c89d87d1d |
preempt/dynamic: Fix typo in macro conditional statement
Commit |