# git rev-parse -q --verify 716f4aaa7b48a55c73d632d0657b35342b1fefd7^{commit}
716f4aaa7b48a55c73d632d0657b35342b1fefd7
already have revision, skipping fetch
# git checkout -q -f -B kisskb 716f4aaa7b48a55c73d632d0657b35342b1fefd7
# git clean -qxdf
# < git log -1
# commit 716f4aaa7b48a55c73d632d0657b35342b1fefd7
# Merge: 841c35169323 46f5ab762d04
# Author: Linus Torvalds <torvalds@linux-foundation.org>
# Date:   Mon Feb 12 07:15:45 2024 -0800
# 
#     Merge tag 'vfs-6.8-rc5.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
#     
#     Pull vfs fixes from Christian Brauner:
#     
#      - Fix performance regression introduced by moving the security
#        permission hook out of do_clone_file_range() and into its caller
#        vfs_clone_file_range().
#     
#        This causes the security hook to be called in situation were it
#        wasn't called before as the fast permission checks were left in
#        do_clone_file_range().
#     
#        Fix this by merging the two implementations back together and
#        restoring the old ordering: fast permission checks first, expensive
#        ones later.
#     
#      - Tweak mount_setattr() permission checking so that mount properties on
#        the real rootfs can be changed.
#     
#        When we added mount_setattr() we added additional checks compared to
#        legacy mount(2). If the mount had a parent then verify that the
#        caller and the mount namespace the mount is attached to match and if
#        not make sure that it's an anonymous mount.
#     
#        But the real rootfs falls into neither category. It is neither an
#        anoymous mount because it is obviously attached to the initial mount
#        namespace but it also obviously doesn't have a parent mount. So that
#        means legacy mount(2) allows changing mount properties on the real
#        rootfs but mount_setattr(2) blocks this. This causes regressions (See
#        the commit for details).
#     
#        Fix this by relaxing the check. If the mount has a parent or if it
#        isn't a detached mount, verify that the mount namespaces of the
#        caller and the mount are the same. Technically, we could probably
#        write this even simpler and check that the mount namespaces match if
#        it isn't a detached mount. But the slightly longer check makes it
#        clearer what conditions one needs to think about.
#     
#     * tag 'vfs-6.8-rc5.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
#       fs: relax mount_setattr() permission checks
#       remap_range: merge do_clone_file_range() into vfs_clone_file_range()
# < /opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux-gcc --version
# < /opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux-ld --version
# < git log --format=%s --max-count=1 716f4aaa7b48a55c73d632d0657b35342b1fefd7
# make -s -j 32 ARCH=x86 O=/kisskb/build/linus_x86_64_defconfig_x86_64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux-  x86_64_defconfig
# < make -s -j 32 ARCH=x86 O=/kisskb/build/linus_x86_64_defconfig_x86_64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux-  help
# make -s -j 32 ARCH=x86 O=/kisskb/build/linus_x86_64_defconfig_x86_64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux-  olddefconfig
# make -s -j 32 ARCH=x86 O=/kisskb/build/linus_x86_64_defconfig_x86_64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux-  
Completed OK
# rm -rf /kisskb/build/linus_x86_64_defconfig_x86_64-gcc8
# Build took: 0:02:11.456086