# git rev-parse -q --verify bb5a93aaf25261321db0c499cde7da6ee9d8b164^{commit} bb5a93aaf25261321db0c499cde7da6ee9d8b164 already have revision, skipping fetch # git checkout -q -f -B kisskb bb5a93aaf25261321db0c499cde7da6ee9d8b164 # git clean -qxdf # < git log -1 # commit bb5a93aaf25261321db0c499cde7da6ee9d8b164 # Author: Linus Torvalds # Date: Sun Jul 5 12:50:20 2020 -0700 # # x86/ldt: use "pr_info_once()" instead of open-coding it badly # # Using a mutex for "print this warning only once" is so overdesigned as # to be actively offensive to my sensitive stomach. # # Just use "pr_info_once()" that already does this, although in a # (harmlessly) racy manner that can in theory cause the message to be # printed twice if more than one CPU races on that "is this the first # time" test. # # [ If somebody really cares about that harmless data race (which sounds # very unlikely indeed), that person can trivially fix printk_once() by # using a simple atomic access, preferably with an optimistic non-atomic # test first before even bothering to treat the pointless "make sure it # is _really_ just once" case. # # A mutex is most definitely never the right primitive to use for # something like this. ] # # Yes, this is a small and meaningless detail in a code path that hardly # matters. But let's keep some code quality standards here, and not # accept outrageously bad code. # # Link: https://lore.kernel.org/lkml/CAHk-=wgV9toS7GU3KmNpj8hCS9SeF+A0voHS8F275_mgLhL4Lw@mail.gmail.com/ # Cc: Andy Lutomirski # Cc: Thomas Gleixner # Cc: Peter Zijlstra (Intel) # Signed-off-by: Linus Torvalds # < /opt/cross/kisskb/korg/gcc-8.1.0-nolibc/m68k-linux/bin/m68k-linux-gcc --version # < /opt/cross/kisskb/korg/gcc-8.1.0-nolibc/m68k-linux/bin/m68k-linux-ld --version # < git log --format=%s --max-count=1 bb5a93aaf25261321db0c499cde7da6ee9d8b164 # < make -s -j 80 ARCH=m68k O=/kisskb/build/linus_sun3_defconfig_m68k-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/m68k-linux/bin/m68k-linux- sun3_defconfig WARNING: unmet direct dependencies detected for NEED_MULTIPLE_NODES Depends on [n]: DISCONTIGMEM [=n] || NUMA Selected by [y]: - SINGLE_MEMORY_CHUNK [=y] && MMU [=y] WARNING: unmet direct dependencies detected for NEED_MULTIPLE_NODES Depends on [n]: DISCONTIGMEM [=n] || NUMA Selected by [y]: - SINGLE_MEMORY_CHUNK [=y] && MMU [=y] # < make -s -j 80 ARCH=m68k O=/kisskb/build/linus_sun3_defconfig_m68k-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/m68k-linux/bin/m68k-linux- help # make -s -j 80 ARCH=m68k O=/kisskb/build/linus_sun3_defconfig_m68k-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/m68k-linux/bin/m68k-linux- olddefconfig WARNING: unmet direct dependencies detected for NEED_MULTIPLE_NODES Depends on [n]: DISCONTIGMEM [=n] || NUMA Selected by [y]: - SINGLE_MEMORY_CHUNK [=y] && MMU [=y] WARNING: unmet direct dependencies detected for NEED_MULTIPLE_NODES Depends on [n]: DISCONTIGMEM [=n] || NUMA Selected by [y]: - SINGLE_MEMORY_CHUNK [=y] && MMU [=y] # make -s -j 80 ARCH=m68k O=/kisskb/build/linus_sun3_defconfig_m68k-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/m68k-linux/bin/m68k-linux- In file included from /kisskb/src/arch/m68k/include/asm/atomic.h:7, from /kisskb/src/include/linux/atomic.h:7, from /kisskb/src/include/linux/spinlock.h:460, from /kisskb/src/include/linux/mmzone.h:8, from /kisskb/src/include/linux/gfp.h:6, from /kisskb/src/include/linux/mm.h:10, from /kisskb/src/kernel/acct.c:47: /kisskb/src/kernel/acct.c: In function 'acct_pin_kill': /kisskb/src/arch/m68k/include/asm/cmpxchg.h:137:3: warning: value computed is not used [-Wunused-value] ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), (unsigned long)(o),\ ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ (unsigned long)(n), sizeof(*(ptr)))) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /kisskb/src/include/asm-generic/cmpxchg.h:106:28: note: in expansion of macro 'cmpxchg_local' #define cmpxchg(ptr, o, n) cmpxchg_local((ptr), (o), (n)) ^~~~~~~~~~~~~ /kisskb/src/kernel/acct.c:177:2: note: in expansion of macro 'cmpxchg' cmpxchg(&acct->ns->bacct, pin, NULL); ^~~~~~~ In file included from /kisskb/src/arch/m68k/include/asm/atomic.h:7, from /kisskb/src/include/linux/atomic.h:7, from /kisskb/src/include/linux/spinlock.h:460, from /kisskb/src/include/linux/seqlock.h:36, from /kisskb/src/include/linux/time.h:6, from /kisskb/src/include/linux/stat.h:19, from /kisskb/src/include/linux/module.h:13, from /kisskb/src/net/core/filter.c:20: /kisskb/src/net/core/filter.c: In function 'bpf_clear_redirect_map': /kisskb/src/arch/m68k/include/asm/cmpxchg.h:137:3: warning: value computed is not used [-Wunused-value] ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), (unsigned long)(o),\ ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ (unsigned long)(n), sizeof(*(ptr)))) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /kisskb/src/include/asm-generic/cmpxchg.h:106:28: note: in expansion of macro 'cmpxchg_local' #define cmpxchg(ptr, o, n) cmpxchg_local((ptr), (o), (n)) ^~~~~~~~~~~~~ /kisskb/src/net/core/filter.c:3569:4: note: in expansion of macro 'cmpxchg' cmpxchg(&ri->map, map, NULL); ^~~~~~~ In file included from /kisskb/src/arch/m68k/include/asm/atomic.h:7, from /kisskb/src/include/linux/atomic.h:7, from /kisskb/src/include/linux/spinlock.h:460, from /kisskb/src/include/linux/mmzone.h:8, from /kisskb/src/include/linux/gfp.h:6, from /kisskb/src/include/linux/slab.h:15, from /kisskb/src/fs/posix_acl.c:15: /kisskb/src/fs/posix_acl.c: In function 'get_acl': /kisskb/src/arch/m68k/include/asm/cmpxchg.h:137:3: warning: value computed is not used [-Wunused-value] ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), (unsigned long)(o),\ ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ (unsigned long)(n), sizeof(*(ptr)))) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /kisskb/src/include/asm-generic/cmpxchg.h:106:28: note: in expansion of macro 'cmpxchg_local' #define cmpxchg(ptr, o, n) cmpxchg_local((ptr), (o), (n)) ^~~~~~~~~~~~~ /kisskb/src/fs/posix_acl.c:148:3: note: in expansion of macro 'cmpxchg' cmpxchg(p, sentinel, ACL_NOT_CACHED); ^~~~~~~ In file included from /kisskb/src/arch/m68k/include/asm/atomic.h:7, from /kisskb/src/include/linux/atomic.h:7, from /kisskb/src/include/linux/spinlock.h:460, from /kisskb/src/include/linux/wait.h:9, from /kisskb/src/include/linux/wait_bit.h:8, from /kisskb/src/include/linux/fs.h:6, from /kisskb/src/fs/ocfs2/file.c:13: /kisskb/src/fs/ocfs2/file.c: In function 'ocfs2_file_write_iter': /kisskb/src/arch/m68k/include/asm/cmpxchg.h:79:22: warning: value computed is not used [-Wunused-value] #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr)))) ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /kisskb/src/fs/ocfs2/file.c:2419:3: note: in expansion of macro 'xchg' xchg(&iocb->ki_complete, saved_ki_complete); ^~~~ Completed OK # rm -rf /kisskb/build/linus_sun3_defconfig_m68k-gcc8 # Build took: 0:01:57.135344