# git rev-parse -q --verify 0846dd77c8349ec92ca0079c9c71d130f34cb192^{commit}
0846dd77c8349ec92ca0079c9c71d130f34cb192
already have revision, skipping fetch
# git checkout -q -f -B kisskb 0846dd77c8349ec92ca0079c9c71d130f34cb192
# git clean -qxdf
# < git log -1
# commit 0846dd77c8349ec92ca0079c9c71d130f34cb192
# Author: Shivaprasad G Bhat <sbhat@linux.ibm.com>
# Date:   Tue Feb 13 10:05:22 2024 -0600
# 
#     powerpc/iommu: Fix the missing iommu_group_put() during platform domain attach
#     
#     The function spapr_tce_platform_iommu_attach_dev() is missing to call
#     iommu_group_put() when the domain is already set. This refcount leak
#     shows up with BUG_ON() during DLPAR remove operation as:
#     
#       KernelBug: Kernel bug in state 'None': kernel BUG at arch/powerpc/platforms/pseries/iommu.c:100!
#       Oops: Exception in kernel mode, sig: 5 [#1]
#       LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=8192 NUMA pSeries
#       <snip>
#       Hardware name: IBM,9080-HEX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1060.00 (NH1060_016) hv:phyp pSeries
#       NIP:  c0000000000ff4d4 LR: c0000000000ff4cc CTR: 0000000000000000
#       REGS: c0000013aed5f840 TRAP: 0700   Tainted: G          I         (6.8.0-rc3-autotest-g99bd3cb0d12e)
#       MSR:  8000000000029033 <SF,EE,ME,IR,DR,RI,LE>  CR: 44002402  XER: 20040000
#       CFAR: c000000000a0d170 IRQMASK: 0
#       ...
#       NIP iommu_reconfig_notifier+0x94/0x200
#       LR  iommu_reconfig_notifier+0x8c/0x200
#       Call Trace:
#         iommu_reconfig_notifier+0x8c/0x200 (unreliable)
#         notifier_call_chain+0xb8/0x19c
#         blocking_notifier_call_chain+0x64/0x98
#         of_reconfig_notify+0x44/0xdc
#         of_detach_node+0x78/0xb0
#         ofdt_write.part.0+0x86c/0xbb8
#         proc_reg_write+0xf4/0x150
#         vfs_write+0xf8/0x488
#         ksys_write+0x84/0x140
#         system_call_exception+0x138/0x330
#         system_call_vectored_common+0x15c/0x2ec
#     
#     The patch adds the missing iommu_group_put() call.
#     
#     Fixes: a8ca9fc9134c ("powerpc/iommu: Do not do platform domain attach atctions after probe")
#     Reported-by: Venkat Rao Bagalkote <venkat88@linux.vnet.ibm.com>
#     Closes: https://lore.kernel.org/all/274e0d2b-b5cc-475e-94e6-8427e88e271d@linux.vnet.ibm.com/
#     Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
#     Tested-by: Venkat Rao Bagalkote <venkat88@linux.vnet.ibm.com>
#     Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
#     Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
#     Link: https://msgid.link/170784021983.6249.10039296655906636112.stgit@linux.ibm.com
# < /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 0846dd77c8349ec92ca0079c9c71d130f34cb192
# make -s -j 40 ARCH=powerpc O=/kisskb/build/powerpc-fixes_ppc64le_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  ppc64le_defconfig
Using /kisskb/src/arch/powerpc/configs/ppc64_defconfig as base
Merging /kisskb/src/arch/powerpc/configs/le.config
#
# merged configuration written to .config (needs make)
#
# < make -s -j 40 ARCH=powerpc O=/kisskb/build/powerpc-fixes_ppc64le_defconfig_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_ppc64le_defconfig_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_ppc64le_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_ppc64le_defconfig_powerpc-gcc5
# Build took: 0:01:58.001931