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Fri, 23 Oct 2026 08:19:54 -0700 (PDT) Received: from pathway.suse.cz ([176.114.240.130]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4a2b061ceb7sm9707855e9.6.2026.10.23.08.19.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 23 Oct 2026 08:19:53 -0700 (PDT) Date: Fri, 23 Oct 2026 17:19:52 +0200 From: Petr Mladek To: Harry Hsu , jpoimboe@kernel.org, mbenes@suse.cz, joe.lawrence@redhat.com Cc: jikos@kernel.org, live-patching@vger.kernel.org, shuah@kernel.org, song@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 0/5] livepatch: Fail object initialization on duplicate patched function Message-ID: References: <20260908120325.299649-1-pmladek@suse.com> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260908120325.299649-1-pmladek@suse.com> On Tue 2026-09-08 14:03:20, Petr Mladek wrote: > This is v4 of the patch failing object initialization when it patches > the same underlying function twice through two aliased symbols > (functions sharing one address) in the same object. I wonder how to move forward with this patchset. There seems to be three unresolved problems: 1. How to handle aliased functions when replacing two livepatches with aliased symbols, aka two NOPs on the same stack [1]. My take: I would fix this later on top of scoped atomic replace. The aliased symbols should conflict. 2. Fix the low-level __write_relocate_add() to clean its own mess on failure. My take: I would fix this a follow up patch. 3. Better describe the purpose of klp_write_object_relocs_limited(). Or clean its own mess a better way (code duplication)? My take: This requires v5. [1] https://lore.kernel.org/all/20260908121744.81D641F00A3A@smtp.kernel.org/ [2] https://lore.kernel.org/all/20260908121810.9577A1F00A3A@smtp.kernel.org/ [3] https://lore.kernel.org/all/att3oHvCpVDjDt-h@pathway.suse.cz/ Best Regards, Petr