| Message ID | 20220307182734.289289-1-npiggin@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [1/2] powerpc/64: Bump SIGSTKSZ and MINSIGSTKSZ | expand |
On Tue, 8 Mar 2022 04:27:33 +1000, Nicholas Piggin wrote: > The sad tale of SIGSTKSZ and MINSIGSTKSZ is documented in glibc.git > commit f7c399cff5bd ("PowerPC SIGSTKSZ"), which explains why glibc > does not use the kernel defines for these constants. Since then in > fact there has been a further expansion of the signal stack frame size > on little-endian with linux commit 573ebfa6601f ("powerpc: Increase > stack redzone for 64-bit userspace to 512 bytes"), which has caused > it to exceed even the glibc defines. > > [...] Applied to powerpc/next. [1/2] powerpc/64: Bump SIGSTKSZ and MINSIGSTKSZ https://git.kernel.org/powerpc/c/2f82ec19757f58549467db568c56e7dfff8af283 [2/2] powerpc/signal: Report minimum signal frame size to userspace via AT_MINSIGSTKSZ https://git.kernel.org/powerpc/c/2896b2dff49d0377e4372f470dcddbcb26f2be59 cheers
diff --git a/arch/powerpc/include/uapi/asm/signal.h b/arch/powerpc/include/uapi/asm/signal.h index 04873dd311c2..81fa9d90be80 100644 --- a/arch/powerpc/include/uapi/asm/signal.h +++ b/arch/powerpc/include/uapi/asm/signal.h @@ -62,8 +62,13 @@ typedef struct { #define SA_RESTORER 0x04000000U +#ifdef __powerpc64__ +#define MINSIGSTKSZ 8192 +#define SIGSTKSZ 32768 +#else #define MINSIGSTKSZ 2048 #define SIGSTKSZ 8192 +#endif #include <asm-generic/signal-defs.h>
The sad tale of SIGSTKSZ and MINSIGSTKSZ is documented in glibc.git commit f7c399cff5bd ("PowerPC SIGSTKSZ"), which explains why glibc does not use the kernel defines for these constants. Since then in fact there has been a further expansion of the signal stack frame size on little-endian with linux commit 573ebfa6601f ("powerpc: Increase stack redzone for 64-bit userspace to 512 bytes"), which has caused it to exceed even the glibc defines. Increase MINSIGSTKSZ to 8192 which is double the current glibc value and fits the current stack frame with room to grow. SIGSTKSZ is set to 4x the minimum as convention. glibc will have to be updated as well. Cc: Alan Modra <amodra@gmail.com> Cc: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> --- arch/powerpc/include/uapi/asm/signal.h | 5 +++++ 1 file changed, 5 insertions(+)