diff options
| author |   Nicholas Piggin <npiggin@gmail.com> | 2022-03-08 04:27:34 +1000 |
|---|---|---|
| committer |   Michael Ellerman <mpe@ellerman.id.au> | 2022-05-19 23:11:26 +1000 |
| commit | 2896b2dff49d0377e4372f470dcddbcb26f2be59 (patch) | |
| tree | 854ce287fc7cb79a46ba739fb5981a5a67f2a003 /arch/powerpc/kernel/signal_64.c | |
| parent | powerpc/64: Bump SIGSTKSZ and MINSIGSTKSZ (diff) | |
| download | linux-dev-2896b2dff49d0377e4372f470dcddbcb26f2be59.tar.xz linux-dev-2896b2dff49d0377e4372f470dcddbcb26f2be59.zip | |
powerpc/signal: Report minimum signal frame size to userspace via AT_MINSIGSTKSZ
Implement the AT_MINSIGSTKSZ AUXV entry, allowing userspace to
dynamically size stack allocations in a manner forward-compatible with
new processor state saved in the signal frame
For now these statically find the maximum signal frame size rather than
doing any runtime testing of features to minimise the size.
glibc 2.34 will take advantage of this, as will applications that use
use _SC_MINSIGSTKSZ and _SC_SIGSTKSZ.
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
References: 94b07c1f8c39 ("arm64: signal: Report signal frame size to userspace via auxv")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220307182734.289289-2-npiggin@gmail.com
Diffstat (limited to 'arch/powerpc/kernel/signal_64.c')
| -rw-r--r-- | arch/powerpc/kernel/signal_64.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c index 858fc13b8c51..472596a109e2 100644 --- a/arch/powerpc/kernel/signal_64.c +++ b/arch/powerpc/kernel/signal_64.c @@ -66,6 +66,11 @@ struct rt_sigframe { char abigap[USER_REDZONE_SIZE]; } __attribute__ ((aligned (16))); +unsigned long get_min_sigframe_size_64(void) +{ + return sizeof(struct rt_sigframe) + __SIGNAL_FRAMESIZE; +} + /* * This computes a quad word aligned pointer inside the vmx_reserve array * element. For historical reasons sigcontext might not be quad word aligned, |