On 7/20/2020 11:26 AM, Florian Fainelli wrote: > On 7/20/20 6:04 AM, Greg KH wrote: >> On Thu, Jul 09, 2020 at 12:50:23PM -0700, Florian Fainelli wrote: >>> From: Will Deacon <will.deacon@xxxxxxx> >>> >>> commit 679db70801da9fda91d26caf13bf5b5ccc74e8e8 upstream >>> >>> Some CPUs can speculate past an ERET instruction and potentially perform >>> speculative accesses to memory before processing the exception return. >>> Since the register state is often controlled by a lower privilege level >>> at the point of an ERET, this could potentially be used as part of a >>> side-channel attack. >>> >>> This patch emits an SB sequence after each ERET so that speculation is >>> held up on exception return. >>> >>> Signed-off-by: Will Deacon <will.deacon@xxxxxxx> >>> [florian: Adjust hyp-entry.S to account for the label >>> added change to hyp/entry.S] >>> Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx> >>> --- >>> Changes in v2: >>> >>> - added missing hunk in hyp/entry.S per Will's feedback >> >> What about 4.19.y and 4.14.y trees? I can't take something for 4.9.y >> and then have a regression if someone moves to a newer release, right? > > Sure, send you candidates for 4.14 and 4.19. Greg, did you have a chance to queue those changes for 4.9, 4.14 and 4.19? https://lore.kernel.org/linux-arm-kernel/20200720182538.13304-1-f.fainelli@xxxxxxxxx/ https://lore.kernel.org/linux-arm-kernel/20200720182937.14099-1-f.fainelli@xxxxxxxxx/ https://lore.kernel.org/linux-arm-kernel/20200709195034.15185-1-f.fainelli@xxxxxxxxx/ Thanks -- Florian
