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To: Hyesoo Yu , Hyeonggon Yoo <42.hyeyoo@gmail.com> References: <20250120082908.4162780-1-hyesoo.yu@samsung.com> <20250121005452.GB610565@tiffany> Content-Language: en-US From: Hyeonggon Yoo In-Reply-To: <20250121005452.GB610565@tiffany> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFtrKIsWRmVeSWpSXmKPExsXC9ZZnoe6NP33pBkemKVpM7DGwmLN+DZvF 9W9vGC2eHGhntPjbeYHVYmV3M5vF5jnFFgvblrBYXN41h83i3pr/rBZtn/8BiSUbmSwmrhG1 mN3Yx+jA57Fz1l12jwWbSj02repk89j0aRK7R9fbK0weJ2b8ZvF4cmU6k8fChqnMHov7JrN6 9G1ZxehxZsERdo/Pm+QCeKK4bFJSczLLUov07RK4MpYcXstS8IavYueSI2wNjK08XYycHBIC JhK3Hm5khbFvfH3AAmLzClhKnNjdyAhiswioSlzbfgYqLihxcuYTMFtUQF7i/q0Z7F2MXBzM AptYJNqXHANrEBbwlFj1fgXYUBEBL4mzPR9YQYqEBH4zSvy73c4OkmAWEJe49WQ+UxcjBweb gJbEjs5UkDCngJ5E15GDbBAlZhJdW7sYIWx5ieats5lB5kgILGKXOPenhRniakmJgytusExg FJyF5MBZSFbMQjJrFpJZCxhZVjGKZOaV5SZm5hjrFWdnVOZlVugl5+duYgRG5rLaP5E7GL9d CD7EKMDBqMTDe8CqL12INbGsuDL3EKMEB7OSCK/oh550Id6UxMqq1KL8+KLSnNTiQ4zSHCxK 4rxG38pThATSE0tSs1NTC1KLYLJMHJxSDYx+uWfmlkhoOsimSb/ffGDe7z+aGW9ecx+f/ary zLdkrZlFEgqVKTZnLuWULF2/N/TP28Bvu/vsftrzhimf/johocZ4Ynpwa+TZa9wvo3orWRM/ Jp/ulOdR657WJVXDzTPhxh2f9OnLtcSePz3z+q3Zgc9x3v8d1G6pNglPZl7GeVyhqmWfeaoS S3FGoqEWc1FxIgDlBbJAyAIAAA== X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprFIsWRmVeSWpSXmKPExsXCNUOnRPfGn750g/52EYuJPQYWc9avYbO4 /u0No8WTA+2MFn87L7BarOxuZrPYPKfY4vDck6wWC9uWsFhc3jWHzeLemv+sFm2f/wGJJRuZ LCauEbWY3djH6MDvsXPWXXaPBZtKPTat6mTz2PRpErtH19srTB4nZvxm8XhyZTqTx8KGqcwe i/sms3r0bVnF6LH4xQcmjzMLjrB7fN4kF8AbxWWTkpqTWZZapG+XwJWx5PBaloI3fBU7lxxh a2Bs5eli5OSQEDCRuPH1AQuIzStgKXFidyMjiM0ioCpxbfsZqLigxMmZT8BsUQF5ifu3ZrB3 MXJxMAtsYpFoX3IMrEFYwFNi1fsVrCC2iICXxNmeD6wgRUICvxkl/t1uZwdJMAuIS9x6Mp+p i5GDg01AS2JHZypImFNAT6LryEE2iBIzia6tXYwQtrxE89bZzBMY+WYhuWMWkkmzkLTMQtKy gJFlFaNIZl5ZbmJmjplecXZGZV5mhV5yfu4mRmCMLav9M2kH47fL7ocYBTgYlXh4D1j1pQux JpYVV+YeYpTgYFYS4RX90JMuxJuSWFmVWpQfX1Sak1p8iFGag0VJnNcrPDVBSCA9sSQ1OzW1 ILUIJsvEwSnVwDjhfE3/+Qvftuve339qbqfGmRcioc2r5CwMjBgqWGvnfrVf1fUzoW/Cbj3O h8En44NcfaYqnL3st2zKtXlX07YqGNy1fnRu2rzb5bNf98R2vUk4+Zrxn1/VwaiQ5VUOV73r c1mONFecD1gqyt/GKHfSTUjz9XNTnaiJUdbXaqwPvgyaUVWk+lyJpTgj0VCLuag4EQA+y8Bc rQIAAA== X-CFilter-Loop: Reflected X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 72A0910000D X-Stat-Signature: m3hbzmwi6tqeaozntn1j8duggfmpzaug X-Rspam-User: X-HE-Tag: 1737424090-736825 X-HE-Meta: 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 MSQ0OeA0 KaepZUAak1qg3dYQK5MR5VOKpreGkcGBztGWn45mUuQee5O5RPtdL1wpUlAuaFlG13mBMikAmgeU2uK8NZ2dEEaJfTj9IWN65XNJF/DZghOHlIghueCYdZsJ8tGf0jFr+4xAMozoy5MjHMeIOfhbeiSEukO8zXeejohuEFdXYf/WnRk/VeCkDqrhvRDfBbUIWAQXqO6Egzt7JNUfxUSvNrLbSvjnuUQVUczGvywO3EWUicQnUThQc3c9uh0xkGQ/fNAB4VqwF+R+2bLQwH3JRJgS9Ng== 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 1/21/2025 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: >>> >>> If a slab object is corrupted or an error occurs in its internal >>> value, continuing after restoration may cause other side effects. >>> At this point, it is difficult to debug because the problem occurred >>> in the past. A flag has been added that can cause a panic when there >>> is a problem with the object. >> >> Hi Hyesoo, >> >> I'm concerned about this because it goes against the effort to avoid >> introducing new BUG() calls [1]. >> >> And I think it would be more appropriate to use existing panic_on_warn >> functionality [2] which causes >> a panic on WARN(), rather than introducing a SLUB-specific knob to do >> the same thing. >> >> However SLUB does not call WARN() and uses pr_err() instead when >> reporting an error. >> Vlastimil and I talked about changing it to use WARN() a while ago >> [3], but neither of us >> have done that yet. >> >> Probably you may want to look at it, as it also aligns with your purpose? >> FYI, if you would like to work on it, please make sure that it WARN() >> is suppressed during kunit test. >> >> [1] https://docs.kernel.org/process/deprecated.html#bug-and-bug-on >> [2] https://www.kernel.org/doc/html/v6.9/admin-guide/sysctl/kernel.html#panic-on-warn >> [3] https://lore.kernel.org/linux-mm/d4219cd9-32d3-4697-93b9-6a44bf77d50c@suse.cz >> >> Best, >> Hyeonggon > > 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