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In-Reply-To: <20260123080532.878738-9-christina.schimpe@intel.com> (Christina Schimpe's message of "Fri, 23 Jan 2026 08:05:30 +0000") References: <20260123080532.878738-1-christina.schimpe@intel.com> <20260123080532.878738-9-christina.schimpe@intel.com> X-Attribution: Tom Date: Thu, 19 Feb 2026 10:43:04 -0700 Message-ID: <87ikbs634n.fsf@tromey.com> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - box5379.bluehost.com X-AntiAbuse: Original Domain - sourceware.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - tromey.com X-BWhitelist: no X-Source-IP: 97.122.122.234 X-Source-L: No X-Exim-ID: 1vt83N-00000001onF-2Dga X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: 97-122-122-234.hlrn.qwest.net (bapiya) [97.122.122.234]:38158 X-Source-Auth: tom+tromey.com X-Email-Count: 10 X-Org: HG=bhshared;ORG=bluehost; X-Source-Cap: ZWx5bnJvYmk7ZWx5bnJvYmk7Ym94NTM3OS5ibHVlaG9zdC5jb20= X-Local-Domain: yes X-CMAE-Envelope: MS4xfKp6vVpogWG/ERba7lqN1Ea5Z1ZTyGBjnGVqFPIh7wHP4GRE3Ipg1KZMlvoSyCoyimOYptD+eaOTQ1CfBdeogb1GlZQ8TpsHh8EbmnRG+aM/gIL9K04D j2NC3aq2ZKU2UfCvTpZmTWwt9O1GfrGJhx0UP/DoisKgNEf95ACCYssGHK2lin3rsA8DPh75JITrv6j8hHWgifU9kzg5u2yQhhQ= X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.30 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: gdb-patches-bounces~public-inbox=simark.ca@sourceware.org >>>>> Christina Schimpe writes: > There can be elements on the shadow stack which are not return addresses. > This can happen, for instance, in case of signals on amd64 linux. > The old shadow stack pointer is pushed in a special format with bit 63 set. > |1...old SSP| - Pointer to old pre-signal ssp in sigframe token format > (bit 63 set to 1) > Linux kernel documentation: https://docs.kernel.org/arch/x86/shstk.html > Implement the gdbarch hook is_no_return_shadow_stack_address to detect > this scenario to print the shadow stack backtrace correctly. I read this and didn't see any problems. However you will have to self-approve in the end since I don't really know anything about the arch details. Reviewed-By: Tom Tromey Tom