Linus, here is the first part of the ACCESS_ONCE vs. non-scalar types rework. I deferred the final patch as linux-next already contains new offenders. I will provide the final patch (kernel: tighten rules for ACCESS ONCE) in linux-next after rc1 together with some fixups. This will make sure that any new offenders will get a warning or error when _THEY_ add such code. Last time it was already too late to fixup linux-next before the merge window.
So here are READ_ONCE, ASSIGN_ONCE and a bunch of fixups. I branched away from a patch in kvm/next to avoid a merge conflict. This will result in a slightly different diffstat in case you merge kvm/for-linus first ( 10 files changed, 103 insertions(+), 25 deletions(-)) Christian The following changes since commit 0df1f2487d2f0d04703f142813d53615d62a1da4: Linux 3.18-rc3 (2014-11-02 15:01:51 -0800) are available in the git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/borntraeger/linux.git tags/for-linus for you to fetch changes up to 5de72a2247ac05bde7c89039631b3d0c6186fafb: s390/kvm: REPLACE barrier fixup with READ_ONCE (2014-12-18 09:54:41 +0100) ---------------------------------------------------------------- kernel: Provide READ_ONCE and ASSIGN_ONCE As discussed on LKML http://marc.info/?i=54611D86.4040306%40de.ibm.com ACCESS_ONCE might fail with specific compilers for non-scalar accesses. Here is a set of patches to tackle that problem. The first patch introduce READ_ONCE and ASSIGN_ONCE. If the data structure is larger than the machine word size memcpy is used and a warning is emitted. The next patches fix up several in-tree users of ACCESS_ONCE on non-scalar types. This merge does not yet contain a patch that forces ACCESS_ONCE to work only on scalar types. This is targetted for the next merge window as Linux next already contains new offenders regarding ACCESS_ONCE vs. non-scalar types. ---------------------------------------------------------------- Christian Borntraeger (9): KVM: s390: Fix ipte locking kernel: Provide READ_ONCE and ASSIGN_ONCE mm: replace ACCESS_ONCE with READ_ONCE or barriers x86/spinlock: Replace ACCESS_ONCE with READ_ONCE x86/gup: Replace ACCESS_ONCE with READ_ONCE mips/gup: Replace ACCESS_ONCE with READ_ONCE arm64/spinlock: Replace ACCESS_ONCE READ_ONCE arm/spinlock: Replace ACCESS_ONCE with READ_ONCE s390/kvm: REPLACE barrier fixup with READ_ONCE arch/arm/include/asm/spinlock.h | 4 +-- arch/arm64/include/asm/spinlock.h | 4 +-- arch/mips/mm/gup.c | 2 +- arch/s390/kvm/gaccess.c | 14 ++++---- arch/x86/include/asm/spinlock.h | 8 ++--- arch/x86/mm/gup.c | 2 +- include/linux/compiler.h | 74 +++++++++++++++++++++++++++++++++++++++ mm/gup.c | 2 +- mm/memory.c | 11 +++++- mm/rmap.c | 3 +- 10 files changed, 105 insertions(+), 19 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
