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charset="utf-8" Content-Transfer-Encoding: 8bit Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Proofpoint-GUID: 9Ct_o8rDtQLArhYBPmA5uyjZQ4NPi2XT X-Proofpoint-Spam-Info: AW1haW4tMjYxMDAyMDAzNyBTYWx0ZWRfX2UTk5VRyYoS8 U+5J422M9sYqulVxbKhsNyjqNQ5sJMNTJDbg7tYCjb/LhQp2vyJBWiq5eTclKyE5lJyKs3zMod2 I00/VpxyeO3C6pHIqDWdEGzhhicV/bg= X-Proofpoint-ORIG-GUID: 9Ct_o8rDtQLArhYBPmA5uyjZQ4NPi2XT X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYxMDAyMDAzNyBTYWx0ZWRfX1xlKl2ngey2c 5Hp2g49Ge6QiErCRXOXKMIpk+iDbIywu8htThM1csiNjci9dWSge19TgvDHIcX/fR8Al3KEqSbQ K5JpeWWf/9SO3n+TPrB1nCRXdaNq7JtVWjsUtdLivblOTLccgbjosz6DukL+dYoOCXXuMIuM9f/ guI6wKwZd1j6aZCHw5Tf+dJPapolCGT0hgR6hF0yPeF6XRh9pA447zKTq9JYQ4CRThvTMDL/Zbf EDTh3fSAfKJq95qibtkgxSec6Vu24HJYApZ/lBGe+QttuYRg8HTlfYkUAfjNkrFHktt49v4+EAp KdGHqYKKxMkyPwea8+EIpFz6tLA0U21gvIkpD2xuIQ7je0fbUjGCgKRSF3K6Hdrds8x6z3vN52j TuP5yRbE7nWwICU4i92BWuO9Ox5mO/9Cyzwrfo1Zd0gbP2WTkG54UfzZ2trdLmTZyLML0A6PUyN Z/ONibcaBTCZFtzBmMQ== X-Authority-Analysis: v=2.4 cv=f+jdl+yM c=1 sm=1 tr=0 ts=6abf77e9 cx=c_pps a=RP+M6JBNLl+fLTcSJhASfg==:117 a=xqWC_Br6kY4A:10 a=IkcTkHD0fZMA:10 a=660iZSQnnn4A:10 a=s4-Qcg_JpJYA:10 a=VkNPw1HP01LnGYTKEx00:22 a=u7WPNUs3qKkmUXheDGA7:22 a=gowsoOTTUOVcmtlkKump:22 a=xvfqbYfxAAAA:20 a=VwQbUJbxAAAA:8 a=pGLkceISAAAA:8 a=iwpyHwDBbu1AC0YlxIwA:9 a=QEXdDO2ut3YA:10 a=iS9zxrgQBfv6-_F4QbHw:22 a=bA3UWDv6hWIuX7UZL3qL:22 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1176,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-10-02_02,2026-10-01_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 adultscore=0 phishscore=0 priorityscore=1501 impostorscore=0 suspectscore=0 clxscore=1015 malwarescore=0 bulkscore=0 spamscore=0 lowpriorityscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2609040000 definitions=main-2610020037 Hi Radim, On Tue, 29 Sep 2026 15:12:36 +0000, Radim Krcmar wrote: > Are we sure that B will always be listed in the ISA string when Zba, > Zbb, and Zbs are present? For DT, yes. The binding requires b whenever zba, zbb and zbs are listed, since commit 0cdb7fc1879b ("dt-bindings: riscv: Add B ISA extension description"). For ACPI there is no such check. But B is a ratified RVI extension and RVA23U64 lists it as mandatory [1], so any serious hardware vendor should respect it. Right? If the firmware does not advertise B, why should the kernel correct that for them? This came up in v2 [2], and maybe here I should quote what Conor said in [3], which I agree with: " Part of me wants to know why we should be going to a bunch of effort to cover up for inaccurate devicetrees etc. Garbage in -> garbage out and let them keep the pieces." [1] https://github.com/riscv/riscv-profiles/releases/tag/rva23-rvb23-ratified [2] https://lore.kernel.org/linux-riscv/CAH1PCMa-5W9PsX8cDLUk6-MkcM53HOz2QtaxCHd+XOr7DgH5+w@mail.gmail.com/ [3] https://lore.kernel.org/all/20260604-decency-salaried-4cb69e1c9fa9@spud/ Guodong