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Mon, 10 Feb 2025 00:30:19 -0800 (PST) Date: Mon, 10 Feb 2025 08:30:15 +0000 In-Reply-To: Mime-Version: 1.0 References: X-Mailer: git-send-email 2.48.1.502.g6dc24dfdaf-goog Message-ID: <20250210083017.280937-1-wnliu@google.com> Subject: Re: [PATCH 0/8] unwind, arm64: add sframe unwinder for kernel From: Weinan Liu To: puranjay@kernel.org Cc: indu.bhagat@oracle.com, irogers@google.com, joe.lawrence@redhat.com, jpoimboe@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-toolchains@vger.kernel.org, live-patching@vger.kernel.org, mark.rutland@arm.com, peterz@infradead.org, roman.gushchin@linux.dev, rostedt@goodmis.org, will@kernel.org, wnliu@google.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250210_003021_130856_A8CD13EA X-CRM114-Status: GOOD ( 18.92 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Feb 7, 2025 at 4:16=E2=80=AFAM Puranjay Mohan = wrote: > > Yes, I think we should, but others people could add more to this. >=20 > I have been testing this series with Kpatch and created a PR that works > with this unwinder: https://github.com/dynup/kpatch/pull/1439 >=20 > For the modules, I think we need per module sframe tables that are > initialised when the module is loaded. And the unwinder should use the > module specific table if the IP is in a module's code. >=20 > Have you already started working on it? if not I would like to help and > work on that. >=20 > Thanks, > Puranjay Thanks for updating the arm64 kpatch PR so quickly. So we can use kpatch to test this proposal. I already have a WIP patch to add sframe support to the kernel module. However, it is not yet working. I had trouble unwinding frames for the=20 kernel module using the current algorithm. Indu has likely identified the issue and will be addressing it from the toolchain side. https://sourceware.org/bugzilla/show_bug.cgi?id=3D32666