On Tue, 2016-26-07 at 08:06:01 UTC, Simon Guo wrote:
From: Simon Guo <redacted>
Normally, when MSR[VSX/VR/SPE] bits = 1, the used_vsr/used_vr/used_spe
bit have already been set. However signal frame locates at user space
and it is controlled by user application. It is up to kernel to make
sure used_vsr/used_vr/used_spe(in kernel)=1 and consistent with MSR
bits.
For example, CRIU application, who utilizes sigreturn to restore
checkpointed process, will lead to the case where MSR[VSX] bit is
active in signal frame, but used_vsx bit is not set. (the same applies
to VR/SPE).
This patch will reinforce this at kernel by always setting used_* bit
when MSR related bits are active in signal frame and we are doing
sigreturn.
This patch is based on Ben's Proposal.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Simon Guo <redacted>
Applied to powerpc next, thanks.
https://git.kernel.org/powerpc/c/e1c0d66fcb179a1737b3d5cc11
cheers