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charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20200909215209.GP6583@casper.infradead.org> User-Agent: Mutt/1.14.6 (2020-07-11) X-Rspamd-Queue-Id: AA4ED18229835 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam02 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000080, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Matthew Wilcox writes: >On Wed, Sep 09, 2020 at 10:47:24PM +0100, Chris Down wrote: >> Vlastimil Babka writes: >> > - Exit also on other signals such as SIGABRT, SIGTERM? If I write to drop_caches >> > and think it's too long, I would prefer to kill it by ctrl-c and not just kill >> >> Oh dear, fatal_signal_pending() doesn't consider cases with no more >> userspace instructions due to SIG_DFL on TERM/INT etc, that seems misleading >> :-( I had (naively) believed it internally checks the same set as >> TASK_KILLABLE. >> >> Chuxin, Muchun, can you please make it work using TASK_KILLABLE in a similar >> way to how schedule_timeout_killable and friends do it instead, so that >> other signals will be caught? > >You're mistaken. > > if (sig_fatal(p, sig) && > !(signal->flags & SIGNAL_GROUP_EXIT) && > !sigismember(&t->real_blocked, sig) && > (sig == SIGKILL || !p->ptrace)) { >... > sigaddset(&t->pending.signal, SIGKILL); > >static inline int __fatal_signal_pending(struct task_struct *p) >{ > return unlikely(sigismember(&p->pending.signal, SIGKILL)); >} Oh great, that makes things way easier. Thanks!