# git rev-parse -q --verify 2accfdb7eff65f390c4308b0e9cb7c3fe48ad63c^{commit} 2accfdb7eff65f390c4308b0e9cb7c3fe48ad63c already have revision, skipping fetch # git checkout -q -f -B kisskb 2accfdb7eff65f390c4308b0e9cb7c3fe48ad63c # git clean -qxdf # < git log -1 # commit 2accfdb7eff65f390c4308b0e9cb7c3fe48ad63c # Author: Linus Torvalds # Date: Mon Jul 29 10:58:28 2024 -0700 # # profiling: attempt to remove per-cpu profile flip buffer # # This is the really old legacy kernel profiling code, which has long # since been obviated by "real profiling" (ie 'prof' and company), and # mainly remains as a source of syzbot reports. # # There are anecdotal reports that people still use it for boot-time # profiling, but it's unlikely that such use would care about the old NUMA # optimizations in this code from 2004 (commit ad02973d42: "profile: 512x # Altix timer interrupt livelock fix" in the BK import archive at [1]) # # So in order to head off future syzbot reports, let's try to simplify # this code and get rid of the per-cpu profile buffers that are quite a # large portion of the complexity footprint of this thing (including CPU # hotplug callbacks etc). # # It's unlikely anybody will actually notice, or possibly, as Thomas put # it: "Only people who indulge in nostalgia will notice :)". # # That said, if it turns out that this code is actually actively used by # somebody, we can always revert this removal. Thus the "attempt" in the # summary line. # # [ Note: in a small nod to "the profiling code can cause NUMA problems", # this also removes the "increment the last entry in the profiling array # on any unknown hits" logic. That would account any program counter in # a module to that single counter location, and might exacerbate any # NUMA cacheline bouncing issues ] # # Link: https://lore.kernel.org/all/CAHk-=wgs52BxT4Zjmjz8aNvHWKxf5_ThBY4bYL1Y6CTaNL2dTw@mail.gmail.com/ # Link: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git [1] # Cc: Thomas Gleixner # Cc: Tetsuo Handa # Signed-off-by: Linus Torvalds # < /opt/cross/kisskb/korg/gcc-8.5.0-nolibc/mips-linux/bin/mips-linux-gcc --version # < /opt/cross/kisskb/korg/gcc-8.5.0-nolibc/mips-linux/bin/mips-linux-ld --version # < git log --format=%s --max-count=1 2accfdb7eff65f390c4308b0e9cb7c3fe48ad63c # make -s -j 40 ARCH=mips O=/kisskb/build/linus_allmodconfig_mips-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/mips-linux/bin/mips-linux- allmodconfig # Added to kconfig CONFIG_BUILD_DOCSRC=n # Added to kconfig CONFIG_MODULE_SIG=n # Added to kconfig CONFIG_SAMPLES=n # Added to kconfig CONFIG_MIPS_CPS_NS16550_BASE=0x1b0003f8 # Added to kconfig CONFIG_MIPS_CPS_NS16550_SHIFT=0 # Added to kconfig CONFIG_GCC_PLUGINS=n # Added to kconfig # < make -s -j 40 ARCH=mips O=/kisskb/build/linus_allmodconfig_mips-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/mips-linux/bin/mips-linux- help # make -s -j 40 ARCH=mips O=/kisskb/build/linus_allmodconfig_mips-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/mips-linux/bin/mips-linux- olddefconfig .config:15203:warning: override: reassigning to symbol MIPS_CPS_NS16550_SHIFT # make -s -j 40 ARCH=mips O=/kisskb/build/linus_allmodconfig_mips-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/mips-linux/bin/mips-linux- /kisskb/src/arch/mips/boot/dts/img/boston.dts:128.17-178.5: Warning (interrupt_provider): /pci@14000000/pci2_root@0,0: '#interrupt-cells' found, but node is not an interrupt provider /kisskb/src/arch/mips/boot/dts/img/boston.dts:136.23-177.6: Warning (interrupt_provider): /pci@14000000/pci2_root@0,0/eg20t_bridge@1,0,0: '#interrupt-cells' found, but node is not an interrupt provider arch/mips/boot/dts/img/boston.dtb: Warning (interrupt_map): Failed prerequisite 'interrupt_provider' /kisskb/src/fs/btrfs/inode.c: In function 'btrfs_lookup_dentry': /kisskb/src/fs/btrfs/inode.c:5674:5: error: 'location.type' may be used uninitialized in this function [-Werror=maybe-uninitialized] if (location.type == BTRFS_INODE_ITEM_KEY) { ^ /kisskb/src/fs/btrfs/inode.c:5603:9: error: 'location.objectid' may be used uninitialized in this function [-Werror=maybe-uninitialized] return btrfs_iget_path(ino, root, NULL); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /kisskb/src/fs/btrfs/inode.c:5663:19: note: 'location.objectid' was declared here struct btrfs_key location; ^~~~~~~~ cc1: all warnings being treated as errors make[5]: *** [/kisskb/src/scripts/Makefile.build:244: fs/btrfs/inode.o] Error 1 make[4]: *** [/kisskb/src/scripts/Makefile.build:485: fs/btrfs] Error 2 make[4]: *** Waiting for unfinished jobs.... make[3]: *** [/kisskb/src/scripts/Makefile.build:485: fs] Error 2 make[3]: *** Waiting for unfinished jobs.... make[2]: *** [/kisskb/src/Makefile:1925: .] Error 2 make[1]: *** [/kisskb/src/Makefile:224: __sub-make] Error 2 make: *** [Makefile:224: __sub-make] Error 2 Command 'make -s -j 40 ARCH=mips O=/kisskb/build/linus_allmodconfig_mips-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/mips-linux/bin/mips-linux- ' returned non-zero exit status 2. # rm -rf /kisskb/build/linus_allmodconfig_mips-gcc8 # Build took: 0:10:19.839220