# git rev-parse -q --verify f01c30de86f1047e9bae1b1b1417b0ce8dcd15b1^{commit}
# git fetch -q -n -f git://fs.ozlabs.ibm.com/kernel/linus master
# git rev-parse -q --verify f01c30de86f1047e9bae1b1b1417b0ce8dcd15b1^{commit}
f01c30de86f1047e9bae1b1b1417b0ce8dcd15b1
# git checkout -q -f -B kisskb f01c30de86f1047e9bae1b1b1417b0ce8dcd15b1
# git clean -qxdf
# < git log -1
# commit f01c30de86f1047e9bae1b1b1417b0ce8dcd15b1
# Merge: d9315f5634c9 9b8523423b23
# Author: Linus Torvalds <torvalds@linux-foundation.org>
# Date:   Fri Nov 13 16:07:53 2020 -0800
# 
#     Merge tag 'vfs-5.10-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
#     
#     Pull fs freeze fix and cleanups from Darrick Wong:
#      "A single vfs fix for 5.10, along with two subsequent cleanups.
#     
#       A very long time ago, a hack was added to the vfs fs freeze protection
#       code to work around lockdep complaints about XFS, which would try to
#       run a transaction (which requires intwrite protection) to finalize an
#       xfs freeze (by which time the vfs had already taken intwrite).
#     
#       Fast forward a few years, and XFS fixed the recursive intwrite problem
#       on its own, and the hack became unnecessary. Fast forward almost a
#       decade, and latent bugs in the code converting this hack from freeze
#       flags to freeze locks combine with lockdep bugs to make this reproduce
#       frequently enough to notice page faults racing with freeze.
#     
#       Since the hack is unnecessary and causes thread race errors, just get
#       rid of it completely. Making this kind of vfs change midway through a
#       cycle makes me nervous, but a large enough number of the usual
#       VFS/ext4/XFS/btrfs suspects have said this looks good and solves a
#       real problem vector.
#     
#       And once that removal is done, __sb_start_write is now simple enough
#       that it becomes possible to refactor the function into smaller,
#       simpler static inline helpers in linux/fs.h. The cleanup is
#       straightforward.
#     
#       Summary:
#     
#        - Finally remove the "convert to trylock" weirdness in the fs freezer
#          code. It was necessary 10 years ago to deal with nested
#          transactions in XFS, but we've long since removed that; and now
#          this is causing subtle race conditions when lockdep goes offline
#          and sb_start_* aren't prepared to retry a trylock failure.
#     
#        - Minor cleanups of the sb_start_* fs freeze helpers"
#     
#     * tag 'vfs-5.10-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
#       vfs: move __sb_{start,end}_write* to fs.h
#       vfs: separate __sb_start_write into blocking and non-blocking helpers
#       vfs: remove lockdep bogosity in __sb_start_write
# < /opt/cross/kisskb/korg/gcc-8.1.0-nolibc/x86_64-linux/bin/x86_64-linux-gcc --version
# < /opt/cross/kisskb/korg/gcc-8.1.0-nolibc/x86_64-linux/bin/x86_64-linux-ld --version
# < git log --format=%s --max-count=1 f01c30de86f1047e9bae1b1b1417b0ce8dcd15b1
# < make -s -j 48 ARCH=x86_64 O=/kisskb/build/linus-rand_x86_64-randconfig_x86_64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/x86_64-linux/bin/x86_64-linux-  randconfig
KCONFIG_SEED=0xBBE36677
# Added to kconfig CONFIG_STANDALONE=y
# Added to kconfig CONFIG_PREVENT_FIRMWARE_BUILD=y
# Added to kconfig CONFIG_CC_STACKPROTECTOR_STRONG=n
# Added to kconfig CONFIG_GCC_PLUGINS=n
# Added to kconfig CONFIG_GCC_PLUGIN_CYC_COMPLEXITY=n
# Added to kconfig CONFIG_GCC_PLUGIN_SANCOV=n
# Added to kconfig CONFIG_GCC_PLUGIN_LATENT_ENTROPY=n
# < make -s -j 48 ARCH=x86_64 O=/kisskb/build/linus-rand_x86_64-randconfig_x86_64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/x86_64-linux/bin/x86_64-linux-  help
# make -s -j 48 ARCH=x86_64 O=/kisskb/build/linus-rand_x86_64-randconfig_x86_64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/x86_64-linux/bin/x86_64-linux-  olddefconfig
.config:5881:warning: override: reassigning to symbol STANDALONE
# make -s -j 48 ARCH=x86_64 O=/kisskb/build/linus-rand_x86_64-randconfig_x86_64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/x86_64-linux/bin/x86_64-linux-  
vmlinux.o: warning: objtool: __sev_es_nmi_complete()+0xc0: call to sev_es_wr_ghcb_msr() leaves .noinstr.text section
vmlinux.o: warning: objtool: lock_is_held_type()+0xb: call to lockdep_enabled() leaves .noinstr.text section
vmlinux.o: warning: objtool: syscall_enter_from_user_mode()+0x16: call to test_bit() leaves .noinstr.text section
vmlinux.o: warning: objtool: syscall_enter_from_user_mode_prepare()+0xe: call to test_bit() leaves .noinstr.text section
vmlinux.o: warning: objtool: irqentry_enter_from_user_mode()+0xe: call to test_bit() leaves .noinstr.text section
Completed OK
# rm -rf /kisskb/build/linus-rand_x86_64-randconfig_x86_64-gcc8
# Build took: 0:03:09.147419