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charset=us-ascii Content-Disposition: inline In-Reply-To: <2a1f8ae6-ed2b-4fe8-85af-df64e9c84794@app.fastmail.com> X-Rspamd-Queue-Id: 9193140009 X-Rspam-User: X-Rspamd-Server: rspam04 X-Stat-Signature: jew5hy5nb3niec4kt4ib9xw8udxg1srw X-HE-Tag: 1689965691-273408 X-HE-Meta: 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 wGpFzwwY TNb/kJxX0ENytwPA81PC1tOzB26IyjSgKmK17T0Jlr/cXhYhjQBMqpYVxskMMFDfU+KBc+JBp4eWXrFL0WbeFzCmEON2/5yau/q8Z3SjapLWh2V73GeVJimU6RI+fscZoRyWp+fPAVp8q11YXyAaJ0w5pGqRm9a95ok/35FkclGJylAbIoUSh7F3tEQ== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Jul 21, 2023 at 05:41:20PM +0200, Arnd Bergmann wrote: > On Fri, Jul 21, 2023, at 12:22, Peter Zijlstra wrote: > > --- a/arch/arm/tools/syscall.tbl > > +++ b/arch/arm/tools/syscall.tbl > > @@ -465,3 +465,4 @@ > > 449 common futex_waitv sys_futex_waitv > > 450 common set_mempolicy_home_node sys_set_mempolicy_home_node > > 451 common cachestat sys_cachestat > > +452 common futex_wake sys_futex_wake > > This clashes with __NR_fchmodat2 in linux-next, which also wants number 452. Yeah, I fully expected some collisions :/ Unavoidable. > > --- a/arch/arm64/include/asm/unistd32.h > > +++ b/arch/arm64/include/asm/unistd32.h > > @@ -909,6 +909,8 @@ __SYSCALL(__NR_futex_waitv, sys_futex_wa > > __SYSCALL(__NR_set_mempolicy_home_node, sys_set_mempolicy_home_node) > > #define __NR_cachestat 451 > > __SYSCALL(__NR_cachestat, sys_cachestat) > > +#define __NR_futex_wake 452 > > +__SYSCALL(__NR_futex_wake, sys_futex_wake) > > > > /* > > * Please add new compat syscalls above this comment and update > > Unfortunately, changing this file still requires updating __NR_compat_syscalls > in arch/arm64/include/asm/unistd.h as well. Bah I missed that. I'll go fix it up. Thanks! > > --- a/kernel/sys_ni.c > > +++ b/kernel/sys_ni.c > > @@ -87,6 +87,7 @@ COND_SYSCALL_COMPAT(set_robust_list); > > COND_SYSCALL(get_robust_list); > > COND_SYSCALL_COMPAT(get_robust_list); > > COND_SYSCALL(futex_waitv); > > +COND_SYSCALL(futex_wake); > > COND_SYSCALL(kexec_load); > > COND_SYSCALL_COMPAT(kexec_load); > > COND_SYSCALL(init_module); > > This is fine for the moment, but I wonder if we should start making > futex mandatory at some point. Right now, sparc32 with CONFIG_SMP > cannot support futex because of the lack of atomics in early > sparc processors, but sparc32 glibc actually requires futexes > and consequently only works on uniprocessor machines, on sparc64 > compat mode, or on Leon3 with out of tree patches. PARISC is another 'fun' case.