On Thu, Aug 06, 2020 at 01:00:54PM -0700, Florian Fainelli wrote: > > > 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/ Nope, I was waiting for Will's "ack" for these. thanks, greg k-h
