# git rev-parse -q --verify f2c7e3562b4c4f1699acc1538ebf3e75f5cced35^{commit} f2c7e3562b4c4f1699acc1538ebf3e75f5cced35 already have revision, skipping fetch # git checkout -q -f -B kisskb f2c7e3562b4c4f1699acc1538ebf3e75f5cced35 # git clean -qxdf # < git log -1 # commit f2c7e3562b4c4f1699acc1538ebf3e75f5cced35 # Author: Russell Currey # Date: Fri Mar 10 16:08:34 2023 +1100 # # powerpc/mm: Fix false detection of read faults # # To support detection of read faults with Radix execute-only memory, the # vma_is_accessible() check in access_error() (which checks for PROT_NONE) # was replaced with a check to see if VM_READ was missing, and if so, # returns true to assert the fault was caused by a bad read. # # This is incorrect, as it ignores that both VM_WRITE and VM_EXEC imply # read on powerpc, as defined in protection_map[]. This causes mappings # containing VM_WRITE or VM_EXEC without VM_READ to misreport the cause of # page faults, since the MMU is still allowing reads. # # Correct this by restoring the original vma_is_accessible() check for # PROT_NONE mappings, and adding a separate check for Radix PROT_EXEC-only # mappings. # # Fixes: 395cac7752b9 ("powerpc/mm: Support execute-only memory on the Radix MMU") # Reported-by: Michal Suchánek # Link: https://lore.kernel.org/r/20230308152702.GR19419@kitsune.suse.cz # Tested-by: Benjamin Gray # Signed-off-by: Russell Currey # Signed-off-by: Michael Ellerman # Link: https://msgid.link/20230310050834.63105-1-ruscur@russell.cc # < /opt/cross/kisskb/korg/gcc-12.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc --version # < /opt/cross/kisskb/korg/gcc-12.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux-ld --version # < git log --format=%s --max-count=1 f2c7e3562b4c4f1699acc1538ebf3e75f5cced35 # < make -s -j 160 ARCH=powerpc O=/kisskb/build/powerpc-fixes_powernv_defconfig+NO_RADIX_powerpc-gcc12 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-12.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux- powernv_defconfig # Added to kconfig CONFIG_PPC_RADIX_MMU=n # < make -s -j 160 ARCH=powerpc O=/kisskb/build/powerpc-fixes_powernv_defconfig+NO_RADIX_powerpc-gcc12 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-12.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux- help # make -s -j 160 ARCH=powerpc O=/kisskb/build/powerpc-fixes_powernv_defconfig+NO_RADIX_powerpc-gcc12 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-12.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux- olddefconfig # make -s -j 160 ARCH=powerpc O=/kisskb/build/powerpc-fixes_powernv_defconfig+NO_RADIX_powerpc-gcc12 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-12.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux- Completed OK # rm -rf /kisskb/build/powerpc-fixes_powernv_defconfig+NO_RADIX_powerpc-gcc12 # Build took: 0:04:05.693726