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. -- Florian
