On Thu, Apr 16, 2020 at 02:30:36PM +0200, Christian Borntraeger wrote: > > On 15.04.20 18:52, Will Deacon wrote: > > Hi everyone, > > > > This is version three of the patches I previously posted for improving > > the code generation of READ_ONCE() and moving the minimum GCC version > > to 4.8: > > > > RFC: https://lore.kernel.org/lkml/20200110165636.28035-1-will@xxxxxxxxxx > > v2: https://lore.kernel.org/lkml/20200123153341.19947-1-will@xxxxxxxxxx > > > > Although v2 was queued up by Peter in -tip, it was found to break the > > build for m68k and sparc32. We fixed m68k during the merge window and > > I've since posted patches to fix sparc32 here: > > > > https://lore.kernel.org/lkml/20200414214011.2699-1-will@xxxxxxxxxx > > > > This series is a refresh on top of 5.7-rc1, the main changes being: > > > > * Fix another issue where 'const' is assigned to non-const via > > WRITE_ONCE(), this time in the tls code > > > > * Fix READ_ONCE_NOCHECK() abuse in arm64 checksum code > > > > * Added Reviewed-bys and Acks from v2 > > > > Hopefully this can be considered for 5.8, along with the sparc32 changes. > > > > Cheers, > > > > Will > > > > Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> > > Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> > > Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> > > Cc: Segher Boessenkool <segher@xxxxxxxxxxxxxxxxxxx> > > Cc: Christian Borntraeger <borntraeger@xxxxxxxxxx> > > Cc: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx> > > Cc: Arnd Bergmann <arnd@xxxxxxxx> > > Cc: Peter Oberparleiter <oberpar@xxxxxxxxxxxxx> > > Cc: Masahiro Yamada <masahiroy@xxxxxxxxxx> > > Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> > > > > I gave this series a try and s390 seems to compile fine and it also seems to > properly compile the the ipte_unlock_siif function in arch/s390/kvm/gaccess.c > This function was miscompiled with gcc4.6 and the trigger for replacing > ACCESS_ONCE with READ_ONCE That's good to hear, thanks Christian! Will