PKEY_ALLOW_ALL is meant to represent the pkey register value that allows
all accesses (enables all pkeys). However its current naming suggests
that the value applies to *one* key only (like PKEY_DISABLE_ACCESS for
instance).
Rename PKEY_ALLOW_ALL to PKEY_REG_ALLOW_ALL to avoid such
misunderstanding. This is consistent with the PKEY_REG_ALLOW_NONE macro
introduced by commit 6e182dc9f2 ("selftests/mm: Use generic pkey
register manipulation").
Link: https://lkml.kernel.org/r/20241209095019.1732120-13-kevin.brodsky@arm.com
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Aruna Ramakrishna <aruna.ramakrishna@oracle.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Joey Gouly <joey.gouly@arm.com>
Cc: Keith Lucas <keith.lucas@oracle.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Headers should not define non-inline functions, as this prevents them from
being included more than once in a given program. pkey-helpers.h and the
arch-specific headers it includes currently define multiple such
non-inline functions.
In most cases those functions can simply be made inline - this patch does
just that. read_ptr() is an exception as it must not be inlined. Since
it is only called from protection_keys.c, we just move it there.
Link: https://lkml.kernel.org/r/20241209095019.1732120-9-kevin.brodsky@arm.com
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Aruna Ramakrishna <aruna.ramakrishna@oracle.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Joey Gouly <joey.gouly@arm.com>
Cc: Keith Lucas <keith.lucas@oracle.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Since commit 49f59573e9 ("selftests/mm: Enable pkey_sighandler_tests
on arm64"), pkey_sighandler_tests.c (which includes pkey-arm64.h via
pkey-helpers.h) ends up compiled for arm64. Since it doesn't use
aarch64_write_signal_pkey(), the compiler warns:
In file included from pkey-helpers.h:106,
from pkey_sighandler_tests.c:31:
pkey-arm64.h:130:13: warning: ‘aarch64_write_signal_pkey’ defined but not used [-Wunused-function]
130 | static void aarch64_write_signal_pkey(ucontext_t *uctxt, u64 pkey)
| ^~~~~~~~~~~~~~~~~~~~~~~~~
Make the aarch64_write_signal_pkey() a 'static inline void' function to
avoid the compiler warning.
Fixes: f5b5ea51f7 ("selftests: mm: make protection_keys test work on arm64")
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Joey Gouly <joey.gouly@arm.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Reviewed-by: Kevin Brodsky <kevin.brodsky@arm.com>
Link: https://lore.kernel.org/r/20241108110549.1185923-1-catalin.marinas@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
pkey_sighandler_tests.c currently hardcodes x86 PKRU encodings. The
first step towards running those tests on arm64 is to abstract away
the pkey register values.
Since those tests want to deny access to all keys except a few,
we have each arch define PKEY_REG_ALLOW_NONE, the pkey register value
denying access to all keys. We then use the existing set_pkey_bits()
helper to grant access to specific keys.
Because pkeys may also remove the execute permission on arm64, we
need to be a little careful: all code is mapped with pkey 0, and we
need it to remain executable. pkey_reg_restrictive_default() is
introduced for that purpose: the value it returns prevents RW access
to all pkeys, but retains X permission for pkey 0.
test_pkru_preserved_after_sigusr1() only checks that the pkey
register value remains unchanged after a signal is delivered, so the
particular value is irrelevant. We enable pkey 0 and a few more
arbitrary keys in the smallest range available on all architectures
(8 keys on arm64).
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/r/20241029144539.111155-5-kevin.brodsky@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The encoding of the pkey register differs on arm64, than on x86/ppc. On those
platforms, a bit in the register is used to disable permissions, for arm64, a
bit enabled in the register indicates that the permission is allowed.
This drops two asserts of the form:
assert(read_pkey_reg() <= orig_pkey_reg);
Because on arm64 this doesn't hold, due to the encoding.
The pkey must be reset to both access allow and write allow in the signal
handler. pkey_access_allow() works currently for PowerPC as the
PKEY_DISABLE_ACCESS and PKEY_DISABLE_WRITE have overlapping bits set.
Access to the uc_mcontext is abstracted, as arm64 has a different structure.
Signed-off-by: Joey Gouly <joey.gouly@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/r/20240822151113.1479789-27-joey.gouly@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
