# 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 <ruscur@russell.cc>
# 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 <msuchanek@suse.de>
#     Link: https://lore.kernel.org/r/20230308152702.GR19419@kitsune.suse.cz
#     Tested-by: Benjamin Gray <bgray@linux.ibm.com>
#     Signed-off-by: Russell Currey <ruscur@russell.cc>
#     Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
#     Link: https://msgid.link/20230310050834.63105-1-ruscur@russell.cc
# < /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 f2c7e3562b4c4f1699acc1538ebf3e75f5cced35
# < make -s -j 40 ARCH=powerpc O=/kisskb/build/powerpc-fixes_ppc64_defconfig+NO_ALTIVEC_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  ppc64_defconfig
# Added to kconfig CONFIG_ALTIVEC=n
# Added to kconfig CONFIG_PPC_TRANSACTIONAL_MEM=n
# < make -s -j 40 ARCH=powerpc O=/kisskb/build/powerpc-fixes_ppc64_defconfig+NO_ALTIVEC_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  help
# make -s -j 40 ARCH=powerpc O=/kisskb/build/powerpc-fixes_ppc64_defconfig+NO_ALTIVEC_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  olddefconfig
# make -s -j 40 ARCH=powerpc O=/kisskb/build/powerpc-fixes_ppc64_defconfig+NO_ALTIVEC_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  
/kisskb/src/fs/btrfs/send.c: In function 'get_cur_inode_state':
/kisskb/src/fs/btrfs/send.c:1902:23: warning: 'right_gen' may be used uninitialized in this function [-Wmaybe-uninitialized]
   if (left_gen == gen && right_gen == gen) {
                       ^
/kisskb/src/fs/btrfs/send.c: At top level:
cc1: warning: unrecognized command line option '-Wno-shift-negative-value'
Completed OK
# rm -rf /kisskb/build/powerpc-fixes_ppc64_defconfig+NO_ALTIVEC_powerpc-gcc5
# Build took: 0:02:30.139209