Commit ad2daa85 authored by Mark Rutland's avatar Mark Rutland Committed by Catalin Marinas

arm64: entry32: remove pointless register assignment

We currently set x27 in compat_sys_sigreturn_wrapper and
compat_sys_rt_sigreturn_wrapper, similarly to what we do with r8/why on
32-bit ARM, in an attempt to prevent sigreturns from being restarted.

However, on arm64 we have always used pt_regs::syscallno for syscall
restarting (for both native and compat tasks), and x27 is never
inspected again before being overwritten in kernel_exit.

This patch removes the pointless register assignments.
Signed-off-by: default avatarMark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent 1b42804d
...@@ -32,13 +32,11 @@ ...@@ -32,13 +32,11 @@
ENTRY(compat_sys_sigreturn_wrapper) ENTRY(compat_sys_sigreturn_wrapper)
mov x0, sp mov x0, sp
mov x27, #0 // prevent syscall restart handling (why)
b compat_sys_sigreturn b compat_sys_sigreturn
ENDPROC(compat_sys_sigreturn_wrapper) ENDPROC(compat_sys_sigreturn_wrapper)
ENTRY(compat_sys_rt_sigreturn_wrapper) ENTRY(compat_sys_rt_sigreturn_wrapper)
mov x0, sp mov x0, sp
mov x27, #0 // prevent syscall restart handling (why)
b compat_sys_rt_sigreturn b compat_sys_rt_sigreturn
ENDPROC(compat_sys_rt_sigreturn_wrapper) ENDPROC(compat_sys_rt_sigreturn_wrapper)
......
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