# git rev-parse -q --verify 6457f42eb3f6e9552366631bd5aeb096ae5f599a^{commit}
6457f42eb3f6e9552366631bd5aeb096ae5f599a
already have revision, skipping fetch
# git checkout -q -f -B kisskb 6457f42eb3f6e9552366631bd5aeb096ae5f599a
# git clean -qxdf
# < git log -1
# commit 6457f42eb3f6e9552366631bd5aeb096ae5f599a
# Author: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
# Date:   Wed May 15 15:15:23 2019 +0530
# 
#     powerpc/mm: Drop VM_BUG_ON in get_region_id()
#     
#     We call get_region_id() without validating the ea value. That means
#     with a wrong ea value we hit the BUG as below.
#     
#       kernel BUG at arch/powerpc/include/asm/book3s/64/hash.h:129!
#       Oops: Exception in kernel mode, sig: 5 [#1]
#       LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
#       CPU: 0 PID: 3937 Comm: access_tests Not tainted 5.1.0
#       ....
#       NIP [c00000000007ba20] do_slb_fault+0x70/0x320
#       LR [c00000000000896c] data_access_slb_common+0x15c/0x1a0
#     
#     Fix this by removing the VM_BUG_ON. All callers make sure the returned
#     region id is valid and error out otherwise.
#     
#     Fixes: 0034d395f89d ("powerpc/mm/hash64: Map all the kernel regions in the same 0xc range")
#     Reported-by: Andrew Donnellan <ajd@linux.ibm.com>
#     Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.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 6457f42eb3f6e9552366631bd5aeb096ae5f599a
# < make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-fixes_44x_redwood_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  44x/redwood_defconfig
# make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-fixes_44x_redwood_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  
<stdin>:1388:2: warning: #warning syscall open_tree not implemented [-Wcpp]
<stdin>:1391:2: warning: #warning syscall move_mount not implemented [-Wcpp]
<stdin>:1394:2: warning: #warning syscall fsopen not implemented [-Wcpp]
<stdin>:1397:2: warning: #warning syscall fsconfig not implemented [-Wcpp]
<stdin>:1400:2: warning: #warning syscall fsmount not implemented [-Wcpp]
<stdin>:1403:2: warning: #warning syscall fspick not implemented [-Wcpp]
Completed OK
# rm -rf /kisskb/build/powerpc-fixes_44x_redwood_defconfig_powerpc-gcc5
# Build took: 0:00:35.807688