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author | Andreas Larsson <andreas@gaisler.com> | 2021-02-04 19:23:41 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2021-02-19 03:15:11 +0300 |
commit | c599a7821be7952033727a30e93bd2d053073c78 (patch) | |
tree | df9b674c803fc84f332c502a184f27a3e99023db /arch/sparc/kernel/entry.S | |
parent | bda166930c37604ffa93f2425426af6921ec575a (diff) | |
download | linux-c599a7821be7952033727a30e93bd2d053073c78.tar.xz |
sparc32: Preserve clone syscall flags argument for restarts due to signals
This fixes a bug where a clone syscall that is restarted due to a
pending signal is restarted with garbage in the register %o0 that holds
the clone flags.
This keep the original %i0 of a syscall (as seen from the trap handler)
in %l6 rather than %l5. This is done because for clone (and also qfork)
%l5 is used as a temporary variable in the same register window. Before
this, that temporary value would be the value that was then incorrectly
used as the orig_i0 argument to do_notify_resume.
In order to preserve %l6, the temporary usage of %l6 in ret_sys_call is
changed to use %l5 instead and the setting %l6 to 0 or 1 was removed.
The use of that 0 or 1 value in %l6 was removed in commit
28e6103665301ce60634e8a77f0b657c6cc099de.
Signed-off-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'arch/sparc/kernel/entry.S')
-rw-r--r-- | arch/sparc/kernel/entry.S | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/arch/sparc/kernel/entry.S b/arch/sparc/kernel/entry.S index f636acf3312f..c385c93b39bc 100644 --- a/arch/sparc/kernel/entry.S +++ b/arch/sparc/kernel/entry.S @@ -1009,7 +1009,7 @@ do_syscall: andcc %l5, _TIF_SYSCALL_TRACE, %g0 mov %i4, %o4 bne linux_syscall_trace - mov %i0, %l5 + mov %i0, %l6 2: call %l7 mov %i5, %o5 @@ -1018,16 +1018,15 @@ do_syscall: st %o0, [%sp + STACKFRAME_SZ + PT_I0] ret_sys_call: - ld [%curptr + TI_FLAGS], %l6 + ld [%curptr + TI_FLAGS], %l5 cmp %o0, -ERESTART_RESTARTBLOCK ld [%sp + STACKFRAME_SZ + PT_PSR], %g3 set PSR_C, %g2 bgeu 1f - andcc %l6, _TIF_SYSCALL_TRACE, %g0 + andcc %l5, _TIF_SYSCALL_TRACE, %g0 /* System call success, clear Carry condition code. */ andn %g3, %g2, %g3 - clr %l6 st %g3, [%sp + STACKFRAME_SZ + PT_PSR] bne linux_syscall_trace2 ld [%sp + STACKFRAME_SZ + PT_NPC], %l1 /* pc = npc */ @@ -1042,7 +1041,6 @@ ret_sys_call: sub %g0, %o0, %o0 or %g3, %g2, %g3 st %o0, [%sp + STACKFRAME_SZ + PT_I0] - mov 1, %l6 st %g3, [%sp + STACKFRAME_SZ + PT_PSR] bne linux_syscall_trace2 ld [%sp + STACKFRAME_SZ + PT_NPC], %l1 /* pc = npc */ |