Buildresult: powerpc-fixes/ep88xc_defconfig/powerpc-gcc5 built on Jun 4 2019, 01:32

kisskb

Revisions | Branches | Compilers | Configs | Build Results | Build Failures |

Status:	OK
Date/Time:	Jun 4 2019, 01:32
Duration:	0:00:20.690429
Builder:	ka4
Revision:	powerpc/64s: Fix THP PMD collapse serialisation (`f41c880e164dc3c9fc3eff6ed27e97583af41986)`
Target:	powerpc-fixes/ep88xc_defconfig/powerpc-gcc5
Branch:	powerpc-fixes
Compiler:	powerpc-gcc5 (powerpc64-linux-gcc (GCC) 5.5.0 / GNU ld (GNU Binutils) 2.29.1.20170915)
Config:	ep88xc_defconfig (download)
Log:	Download original No warnings found in log. Full Log # git rev-parse -q --verify f41c880e164dc3c9fc3eff6ed27e97583af41986^{commit} f41c880e164dc3c9fc3eff6ed27e97583af41986 already have revision, skipping fetch # git checkout -q -f -B kisskb f41c880e164dc3c9fc3eff6ed27e97583af41986 # git clean -qxdf # < git log -1 # commit f41c880e164dc3c9fc3eff6ed27e97583af41986 # Author: Nicholas Piggin <npiggin@gmail.com> # Date: Mon Jun 3 16:05:31 2019 +1000 # # powerpc/64s: Fix THP PMD collapse serialisation # # Commit 1b2443a547f9 ("powerpc/book3s64: Avoid multiple endian # conversion in pte helpers") changed the actual bitwise tests in # pte_access_permitted by using pte_write() and pte_present() helpers # rather than raw bitwise testing _PAGE_WRITE and _PAGE_PRESENT bits. # # The pte_present change now returns true for ptes which are # !_PAGE_PRESENT and _PAGE_INVALID, which is the combination used by # pmdp_invalidate to synchronize access from lock-free lookups. # pte_access_permitted is used by pmd_access_permitted, so allowing GUP # lock free access to proceed with such PTEs breaks this # synchronisation. # # This bug has been observed on HPT host, with random crashes and # corruption in guests, usually together with bad PMD messages in the # host. # # Fix this by adding an explicit check in pmd_access_permitted, and # documenting the condition explicitly. # # The pte_write() change should be okay, and would prevent GUP from # falling back to the slow path when encountering savedwrite ptes, which # matches what x86 (that does not implement savedwrite) does. # # Fixes: 1b2443a547f9 ("powerpc/book3s64: Avoid multiple endian conversion in pte helpers") # Cc: stable@vger.kernel.org # v4.20+ # Signed-off-by: Nicholas Piggin <npiggin@gmail.com> # Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> # < /opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc --version # < /opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-ld --version # < git log --format=%s --max-count=1 f41c880e164dc3c9fc3eff6ed27e97583af41986 # < make -s -j 120 ARCH=powerpc O=/kisskb/build/powerpc-fixes_ep88xc_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux- ep88xc_defconfig # make -s -j 120 ARCH=powerpc O=/kisskb/build/powerpc-fixes_ep88xc_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux- Completed OK # rm -rf /kisskb/build/powerpc-fixes_ep88xc_defconfig_powerpc-gcc5 # Build took: 0:00:20.690429

© Michael Ellerman 2006-2018.