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charset=us-ascii Content-Disposition: inline In-Reply-To: <20230425222446.170486-1-jim.cromie@gmail.com> X-Rspam-User: X-Rspamd-Queue-Id: C805F2001B X-Rspamd-Server: rspam09 X-Stat-Signature: eu59rgfja6pzydy5urnj77wu6odjqjuc X-HE-Tag: 1682702709-852848 X-HE-Meta: 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 Zhdw5cRn HWyh7KKP4t8wP0B1HOEy8UhvyeLuDi9bAGS68v2yW9KrG+XIbDS/bu+vF+Gjwy82DYFvzkjN/1/iVOeCd9Q/4jjm4O+tNOgRADVqKs4PR7CiKTS0aTAR0f3pHoLHiTjpoOIuukH62dFC3cQHFlAIkMDIoBZ42LgciCekZ6128FseOvDhO3Ncr0vR7bNoRLcaif6r2EX3AiouZB6QvtnjRJ+xQLR+Q7usCLh5XP4Qa+S7aVKsByWUi0/Mip8arTEneH8OVNCs5t04tLYzfvoKPZp8dFmTCnlQ0dDAFMBtf4MQUFc3omqw3P6dAZvTgOXzJypkiZcdYQIjd17aCMyN+4eeePrU5XqSArg3TwDoIqpMdLH3Vu2PC5TN5yEeosT/LohmoU+72fq9ml4U3WSU1bk65VYnwKlWCkrja2ayeDgR+W699mj1JWM36VsEnTNhbm5piApYdufsVus8k6Yvt/o5hn39JTdXm0HaGAlGbmrMy6tM= 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 Tue, Apr 25, 2023 at 04:24:43PM -0600, Jim Cromie wrote: > If format changes are not /sys/** ABI violating, heres 3 minor ones: > > 1st strips "age " from output. This makes the output > idempotent; unchanging until a new leak is reported. > > 2nd adds the backtrace.checksum to the "backtrace:" line. This lets a > user see repeats without actually reading the whole backtrace. So now > the backtrace line looks like this: > > backtrace (ck 603070071): # also see below > > Q: should ck be spelled crc ? it feels more communicative. These all would make sense (and 'crc' sounds better) if they were done from the start. I know there are test scripts out there parsing the kmemleak sysfs file. I can't tell whether these changes would break them. Cc'ing Dmitry, I think syzbot was regularly checking kmemleak (not sure it still does). > NB: with ck exposed, it becomes possible to do a "selective clear", > something like: > > echo drop 603070071 > /sys/kernel/debug/kmemleak > > The 3rd patch takes __init off of kmemleak_test_init(). This fixes a > bare-pointer in the 2nd line of the backtrace below, which previously > looked like: > > [<00000000ef738764>] 0xffffffffc02350a2 > > NB: this happens still/again, after rmmod kmemleak-test. > > unreferenced object 0xffff888005d9ca40 (size 32): > comm "modprobe", pid 412, jiffies 4294703300 > hex dump (first 32 bytes): > 00 cd d9 05 80 88 ff ff 40 cf d9 05 80 88 ff ff ........@....... > 14 a7 c4 f6 7d f9 87 10 00 00 00 00 00 00 00 00 ....}........... > backtrace (ck 1354775490): > [<000000002c474f61>] kmalloc_trace+0x26/0x90 > [<00000000b26599c1>] kmemleak_test_init+0x58/0x2d0 [kmemleak_test] > [<0000000044d13990>] do_one_initcall+0x43/0x210 > [<00000000131bc505>] do_init_module+0x4a/0x210 > [<00000000b2902890>] __do_sys_finit_module+0x93/0xf0 > [<00000000673fdce2>] do_syscall_64+0x34/0x80 > [<00000000357a2d80>] entry_SYSCALL_64_after_hwframe+0x46/0xb0 -- Catalin