summaryrefslogtreecommitdiffstats
path: root/drivers/bus/arm-cci.c
diff options
context:
space:
mode:
authorRaoni Fassina Firmino <raoni@linux.ibm.com>2021-02-01 21:05:05 +0100
committerMichael Ellerman <mpe@ellerman.id.au>2021-02-02 12:14:41 +0100
commit24321ac668e452a4942598533d267805f291fdc9 (patch)
tree2c024465409db4444b46630af443bdcc5a8fa535 /drivers/bus/arm-cci.c
parentpowerpc/vdso64: remove meaningless vgettimeofday.o build rule (diff)
downloadlinux-24321ac668e452a4942598533d267805f291fdc9.tar.xz
linux-24321ac668e452a4942598533d267805f291fdc9.zip
powerpc/64/signal: Fix regression in __kernel_sigtramp_rt64() semantics
Commit 0138ba5783ae ("powerpc/64/signal: Balance return predictor stack in signal trampoline") changed __kernel_sigtramp_rt64() VDSO and trampoline code, and introduced a regression in the way glibc's backtrace()[1] detects the signal-handler stack frame. Apart from the practical implications, __kernel_sigtramp_rt64() was a VDSO function with the semantics that it is a function you can call from userspace to end a signal handling. Now this semantics are no longer valid. I believe the aforementioned change affects all releases since 5.9. This patch tries to fix both the semantics and practical aspect of __kernel_sigtramp_rt64() returning it to the previous code, whilst keeping the intended behaviour of 0138ba5783ae by adding a new symbol to serve as the jump target from the kernel to the trampoline. Now the trampoline has two parts, a new entry point and the old return point. [1] https://lists.ozlabs.org/pipermail/linuxppc-dev/2021-January/223194.html Fixes: 0138ba5783ae ("powerpc/64/signal: Balance return predictor stack in signal trampoline") Cc: stable@vger.kernel.org # v5.9+ Signed-off-by: Raoni Fassina Firmino <raoni@linux.ibm.com> Acked-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Minor tweaks to change log formatting, add stable tag] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210201200505.iz46ubcizipnkcxe@work-tp
Diffstat (limited to 'drivers/bus/arm-cci.c')
0 files changed, 0 insertions, 0 deletions