If you use git, you can easily cherry-pick the fix from HardenedBSD: https://github.com/HardenedBSD/hardenedBSD/commit/e7ee74598b987fdc702614668b7ea85884289cf1
On Tue, Aug 11, 2020 at 02:31:26PM +0200, Mateusz Guzik wrote: > Hi. This remains unfixed. > > On 8/4/20, Emmanuel Vadot <m...@bidouilliste.com> wrote: > > On Tue, 4 Aug 2020 13:11:02 -0500 > > Alan Cox <a...@rice.edu> wrote: > > > >> > >> On 8/4/20 10:25 AM, Emmanuel Vadot wrote: > >> > Author: manu > >> > Date: Tue Aug 4 15:25:22 2020 > >> > New Revision: 363842 > >> > URL: https://svnweb.freebsd.org/changeset/base/363842 > >> > > >> > Log: > >> > linuxkpi: Add clear_bit_unlock > >> > > >> > This calls clear_bit and adds a memory barrier. > >> > > >> > Sponsored by: The FreeBSD Foundation > >> > > >> > Reviewed by: hselasky > >> > MFC after: 1 week > >> > Differential Revision: https://reviews.freebsd.org/D25943 > >> > > >> > Modified: > >> > head/sys/compat/linuxkpi/common/include/linux/bitops.h > >> > > >> > Modified: head/sys/compat/linuxkpi/common/include/linux/bitops.h > >> > ============================================================================== > >> > --- head/sys/compat/linuxkpi/common/include/linux/bitops.h Tue Aug > >> > 4 > >> > 15:00:02 2020 (r363841) > >> > +++ head/sys/compat/linuxkpi/common/include/linux/bitops.h Tue Aug > >> > 4 > >> > 15:25:22 2020 (r363842) > >> > @@ -275,6 +275,13 @@ find_next_zero_bit(const unsigned long *addr, > >> > unsigned > >> > #define test_bit(i, a) > >> > \ > >> > !!(READ_ONCE(((volatile const unsigned long *)(a))[BIT_WORD(i)]) & > >> > BIT_MASK(i)) > >> > > >> > +static inline void > >> > +clear_bit_unlock(long bit, volatile unsigned long *var) > >> > +{ > >> > + clear_bit(bit, var); > >> > + wmb(); > >> > >> > >> For an unlock operation, the memory barrier should come before the > >> clear_bit() call, not after.?? See, for example, the alpha implementation > >> in Linux.?? Also, the correct "spelling" for this memory barrier in > >> FreeBSD would be atomic_thread_fence_rel(). See, for example, the > >> comment at the top of sys/amd64/include/atomic.h. > > > > Ah yes, thanks. I probably got lost looking for the linux implem but > > that does make sense, I'll fix that probably tomorow. > > > > Thanks. > > > >> > >> > +} > >> > + > >> > static inline int > >> > test_and_clear_bit(long bit, volatile unsigned long *var) > >> > { > > > > > > -- > > Emmanuel Vadot <m...@bidouilliste.com> <m...@freebsd.org> > > > > > -- > Mateusz Guzik <mjguzik gmail.com> > _______________________________________________ > svn-src-...@freebsd.org mailing list > https://lists.freebsd.org/mailman/listinfo/svn-src-all > To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org" -- Shawn Webb Cofounder / Security Engineer HardenedBSD GPG Key ID: 0xFF2E67A277F8E1FA GPG Key Fingerprint: D206 BB45 15E0 9C49 0CF9 3633 C85B 0AF8 AB23 0FB2 https://git-01.md.hardenedbsd.org/HardenedBSD/pubkeys/src/branch/master/Shawn_Webb/03A4CBEBB82EA5A67D9F3853FF2E67A277F8E1FA.pub.asc
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