Uninstrument arch/x86/platform/pvh/enlighten.c: KASAN has not been setup
_this_ early in the boot process.
Steps to reproduce:
make allnoconfig
make sure CONFIG_AMD_MEM_ENCRYPT is disabled
AMD_MEM_ENCRYPT independently uninstruments lib/string.o
so PVH boot code calls into uninstrumented memset() and
memcmp() which can make the bug disappear depending on
the compiler.
enable CONFIG_PVH
enable CONFIG_KASAN
enable serial console
this is fun exercise if you never done it from nothing :^)
make
qemu-system-x86_64 \
-enable-kvm \
-cpu host \
-smp cpus=1 \
-m 4096 \
-serial stdio \
-kernel vmlinux \
-append 'console=ttyS0 ignore_loglevel'
Messages on serial console will easily tell OK kernel from unbootable
kernel. In bad case qemu hangs in an infinite loop stroboscoping
"SeaBIOS" message.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Juergen Gross <jgross@suse.com>
Message-ID: <20240802154253.482658-1-adobriyan@gmail.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
For certain applications it is desirable to rapidly boot a KVM virtual
machine. In cases where legacy hardware and software support within the
guest is not needed, Qemu should be able to boot directly into the
uncompressed Linux kernel binary without the need to run firmware.
There already exists an ABI to allow this for Xen PVH guests and the ABI
is supported by Linux and FreeBSD:
https://xenbits.xen.org/docs/unstable/misc/pvh.html
This patch enables Qemu to use that same entry point for booting KVM
guests.
Signed-off-by: Maran Wilson <maran.wilson@oracle.com>
Suggested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Suggested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Once hypervisors other than Xen start using the PVH entry point for
starting VMs, we would like the option of being able to compile PVH entry
capable kernels without enabling CONFIG_XEN and all the code that comes
along with that. To allow that, we are moving the PVH code out of Xen and
into files sitting at a higher level in the tree.
This patch is not introducing any code or functional changes, just moving
files from one location to another.
Signed-off-by: Maran Wilson <maran.wilson@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
