sparc: Remove unwind information from signal return stubs [BZ #31244]

The functions were previously written in C, but were not compiled
with unwind information. The ENTRY/END macros includes .cfi_startproc
and .cfi_endproc which adds unwind information. This caused the
tests cleanup-8 and cleanup-10 in the GCC testsuite to fail.
This patch adds a version of the ENTRY/END macros without the
CFI instructions that can be used instead.

sigaction registers a restorer address that is located two instructions
before the stub function. This patch adds a two instruction padding to
avoid that the unwinder accesses the unwind information from the function
that the linker has placed right before it in memory. This fixes an issue
with pthread_cancel that caused tst-mutex8-static (and other tests) to fail.

Signed-off-by: Daniel Cederman <cederman@gaisler.com>
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
This commit is contained in:
Daniel Cederman 2024-01-16 09:31:41 +01:00 committed by Adhemerval Zanella
parent 82a35070ec
commit 7bd06985c0
2 changed files with 16 additions and 4 deletions

View File

@ -76,6 +76,15 @@ C_LABEL(name) \
cfi_endproc; \
.size name, . - name
#define ENTRY_NOCFI(name) \
.align 4; \
.global C_SYMBOL_NAME(name); \
.type name, @function; \
C_LABEL(name)
#define END_NOCFI(name) \
.size name, . - name
#undef LOC
#define LOC(name) .L##name

View File

@ -23,12 +23,15 @@
[1] https://lkml.org/lkml/2016/5/27/465 */
ENTRY (__rt_sigreturn_stub)
nop
nop
ENTRY_NOCFI (__rt_sigreturn_stub)
mov __NR_rt_sigreturn, %g1
ta 0x10
END (__rt_sigreturn_stub)
END_NOCFI (__rt_sigreturn_stub)
ENTRY (__sigreturn_stub)
ENTRY_NOCFI (__sigreturn_stub)
mov __NR_sigreturn, %g1
ta 0x10
END (__sigreturn_stub)
END_NOCFI (__sigreturn_stub)