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Fri, 31 Jan 2025 18:04:47 -0800 (PST) Content-Type: text/plain; charset=us-ascii Precedence: bulk X-Mailing-List: live-patching@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3774.500.171.1.1\)) Subject: Re: [PATCH] livepatch: Avoid hard lockup caused by klp_try_switch_task() From: zhang warden In-Reply-To: Date: Sat, 1 Feb 2025 10:04:32 +0800 Cc: Yafang Shao , Josh Poimboeuf , Jiri Kosina , mbenes@suse.cz, joe.lawrence@redhat.com, live-patching@vger.kernel.org Content-Transfer-Encoding: quoted-printable Message-Id: <86736F95-020D-476F-999C-8666A6B0BC23@gmail.com> References: <20250122085146.41553-1-laoar.shao@gmail.com> To: Petr Mladek X-Mailer: Apple Mail (2.3774.500.171.1.1) > On Jan 31, 2025, at 21:39, Petr Mladek wrote: >=20 > You got it right. I am afraid that it might create a livelock > situation for the livepatch transition. I mean that the check > might almost always break on systems with thousands of processes > and frequently created/exited processes. It always has > to start from the beginning. >=20 > Best Regards, > Petr True. It will easily raise the problem that some important process = cannot successfully finish the target patch state and make the = livepatch-fix unable to work on some key process(which may happen). =20 If this happens, I am sure it would be a nightmare... Best Regards, Wardenjohn