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Peter Anvin" , Andrew Morton , "Liam R. Howlett" , Vlastimil Babka , Lorenzo Stoakes , Paul Walmsley , Palmer Dabbelt , Albert Ou , Conor Dooley , Rob Herring , Krzysztof Kozlowski , Arnd Bergmann , Christian Brauner , Peter Zijlstra , Oleg Nesterov , Eric Biederman , Kees Cook , Jonathan Corbet , Shuah Khan , Jann Horn , Conor Dooley , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-riscv@lists.infradead.org, devicetree@vger.kernel.org, linux-arch@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, alistair.francis@wdc.com, richard.henderson@linaro.org, jim.shu@sifive.com, andybnac@gmail.com, kito.cheng@sifive.com, charlie@rivosinc.com, atishp@rivosinc.com, evan@rivosinc.com, alexghiti@rivosinc.com, samitolvanen@google.com, broonie@kernel.org, rick.p.edgecombe@intel.com Subject: Re: [PATCH v9 14/26] riscv/traps: Introduce software check exception Message-ID: References: <20250204-v5_user_cfi_series-v9-0-b37a49c5205c@rivosinc.com> <20250204-v5_user_cfi_series-v9-14-b37a49c5205c@rivosinc.com> Precedence: bulk X-Mailing-List: linux-arch@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Hi Clement, Thanks for looking at it. Inline On Thu, Feb 06, 2025 at 02:49:09PM +0100, Clément Léger wrote: > > >On 05/02/2025 02:22, Deepak Gupta wrote: >> zicfiss / zicfilp introduces a new exception to priv isa `software check >> exception` with cause code = 18. This patch implements software check >> exception. > >Hey Deepak, > >While not directly related to this patch, is the exception 18 delegation >documented in the SBI doc ? I mean, should we specify that it is always >delegated when implementing FWFT LANDING_PAD/SHADOW_STACK ? I don't think it's document in SBI spec anywhere. Should it be ? In code, opensbi delegates the exception (SW_CHECK) https://github.com/riscv-software-src/opensbi/commit/110524441a827e026db3547ed03c5723b9c9e211 > >Thanks, > >Clément > >>