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To: Hyesoo Yu , Hyeonggon Yoo Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>, kernel_team@skhynix.com, "janghyuck.kim@samsung.com" , Andrew Morton , Jonathan Corbet , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Roman Gushchin , "linux-mm@kvack.org" , "linux-doc@vger.kernel.org" , "linux-kernel@vger.kernel.org" References: <20250120082908.4162780-1-hyesoo.yu@samsung.com> <20250121005452.GB610565@tiffany> <1495dc28-f16c-4990-ad89-2a90b79a80b8@sk.com> <20250121023240.GA645761@tiffany> From: Vlastimil Babka Content-Language: en-US In-Reply-To: <20250121023240.GA645761@tiffany> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Action: no action X-Rspam-User: X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 3E07580010 X-Stat-Signature: t45pbw8odhi35exrdsosz8nhwf36a578 X-HE-Tag: 1737455322-499212 X-HE-Meta: U2FsdGVkX190OH8NzhcKwsU/UKzZHr1krPV73JuCBs2YUl3N3VsUPM0gOi4T36LPr0yViTWZT07UJp3QOwWCg634eIyyP6GrdFtjqRZAKb20GF3ScfLQXh1e4sVPCYxVe2x/pqDOJ/XX3Ggy87PfAfdXQnINmOXxQwem0slcgZwOEG2xqlW6Le1zu/dnCEBGpZZSOAA4ZvcY5MfuIszDdUIUGWEENIiBGsFWUAkGuXJ4wq1uRLtwNcY5V1A0SK9t6VO3ZQrZPnbqGBT2TF9HB1j/vqWnr3FbYn11rb+KFYingz5/02gbS3FA1mDU7rRbYN5zRqGTfnENcVLzfvwrZO9OmVNniJ80MiUpntK/U4QCliU/6cOPzMtMUlilhsXVIYW4DH4QVJpUCAolN+2rvp1PCgtVshq6I4yKHyOJPI1PUpXzaWzIldwlO9YtGAkAi3SCij7qh0s9R9Op+yn/U3dFIoO1/uSvHx0A7UnXAinadEBIUGGve4ZDiS4HgHFh9MOdAmMrLp+kaoRiDOrvJjWdIXEe6+I0EoX2Lxenuzvc1TCxuu2gPADmWZC5wUdDJR9iUgmBbfZzZ822QJOeXXhX5jpf2+ABt5aImPmTGAc70ciPxajHaF4Ps9438F3c68VGV6sR2l18YfBf1JkvZNpAg8Kjd+MeJ69S3b1R36vwQbTUmJoAncSH77xkRG29alNspU5YGecfBLgxkRbw7887FpXwFa9awYvifraLTFpk7fauhZBtwoGebuX+0g8H55GhdYRQxnbB5q1sWWfQAQECVKSnreQX0TGEMVs4rYZ8XGen80yT+d8Z9Jy6XLDK7IpxXaVWRaAdBHlKo6ce957l5YRtJyq/Q27t28WZHbBSwBZAmMGaYkv96Kuq2XSBoY4QTPQZig0i9xTEl0ia+vYzL6WfcE1TdyCHs0EAEYBqzHB69WkOLj696biWMvjfbCtjx+2vdeMkdZ9ccpj Zrjumdcf ufi0JocQ5pAA7/dJ30CF7qgWA4vxF6bXhSmiAgmvU9EjKCB1aff+7/retuHoxNewRDTK5PaQSkPzd5i79nQsGE5+2DnqTDQZiGiqb3CgMq87wHpabazPSDN9TnQmsZXL8jEGIwms9GRhCbzAUPAli0VXRkAz543ZODHulSy5YkDmBf8FVLrwNUND+kP8Hfo2YWaJ3v1gjz1jlvbkVPv5QeaiHnK4UMw6fEMyMILsBfBnBZp2u5n79DMsz+7ALCNuyP1D+6V4lY0LlYBz0Jg4wYksZWrrsvE/16QEXEgj1Rvxsq5z8+YqMOnH4SX+jv5GRxc3F574XP1W64yZrSN4goo73PwsrlXH0fAW7ekV3q3rb+xkxUeao/T2+w0ixfHjjLSTyjU3PgJBh/HLLLjtYmG4tph5M/kUDPQmole0Yyq8cj1cuIEic/Egg1nD9nisuSNPU 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: List-Subscribe: List-Unsubscribe: On 1/21/25 3:32 AM, Hyesoo Yu wrote: > On Tue, Jan 21, 2025 at 10:48:08AM +0900, Hyeonggon Yoo wrote: >> >> >> On 1/21/2025 9:54 AM, Hyesoo Yu wrote: >>> On Tue, Jan 21, 2025 at 12:41:01AM +0900, Hyeonggon Yoo wrote: >>>> On Mon, Jan 20, 2025 at 5:30 PM Hyesoo Yu wrote: >>> >>> Thanks for response. >>> >>> Using warn() instead of panic, is a great idea. >>> Thanks for pointing out what I missed. >> >> Just for clarification, I think changing the common error reporting >> logic (like, slab_bug()) to use WARN() will be preferable to inserting >> new WARN()s at random points, which is what this patch does now. >> >> Best, >> Hyeonggon >> > > Thanks you for clarification. > > Actually, I considered adding BUG_ON() to slab_bug. However if we add BUG_ON() to slab_bug, > it will prevent many meaningful error log from being printed subsequently. > As you know, slab_bug is the log that usually is printed at the biginning of a bug > in the slab. As a result, it would be difficult to figure out the problems based on > the logs during our large-scale test-bed. > > Similary, even if I use WARN() in slab_bug, we won't be able to obtain the logs > when panic_on_warn is enabled. I don't think it is useful to include WARN in slab_bug. > > Instead, I will implement a solution where WARN is only used in slab_fix before > slab object is restored. If I add it to slab_fix, I think warning is suppressed on > kunit test by slab_add_kunit_errors handling. Right, makes sense to only do the WARN() after printing the debugging logs. Thanks. > Thanks, > Regards. > >