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b=H4sIANRdwmUC/x3MQQqAIBBA0avErBswMxddJVqIjTWQGhoSSHdPW r7F/xUyJaYMc1chUeHMMTQMfQf2MGEn5K0ZpJBKSKHRJK8V5kJYTvTmQRu9p3CjVuTM6MSo5QQ tvxI5fv71sr7vBw/DDWdqAAAA To: Catalin Marinas , Will Deacon Cc: Dave Martin , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Mark Brown X-Mailer: b4 0.13-dev-0438c X-Developer-Signature: v=1; a=openpgp-sha256; l=1327; i=broonie@kernel.org; h=from:subject:message-id; bh=fRog9coSpdrDKRPeW6Hy2Z/gSCmjUBq/+m0a/5NTav8=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBlwl4DLTjeWojBDQwiaeCesLKB01RBMye6iqVO9 W/87/JHKN+JATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCZcJeAwAKCRAk1otyXVSH 0F8KB/0dwrDLgl+VpeCMPKSQvsPK0/ZbXt8jR6xLiS04IOvrXQptZgBHtWmY/f5KIQSTdnRkHoj ksAn9CfWWvpUy91iB65q4RxXcGgSE+htmYdXM9ZxdV2RaAzTCVCyjtl6/npVzY4f91tUTx1oqXT h7QwjfMJCTjPfTHtHspOrjSA9WcBOKOqhCTsLxMlYg78TxnaJkSkiloydk3Epp7xUUcDK6JsKjX bfjBKLFnebOVearwBWJ5Dr3c4qGL8DuyQvVtQ5Ur5wu1TT7jL6IFNwu6IfVoQsalQ238+JpdS1H VG2dtOHIhTs2/EjyTMp99SfQqxjOzAw4CpymanzQw5TPUzev X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1790169421771585840 X-GMAIL-MSGID: 1790169421771585840 __SVE_VQ_MAX is defined without comment as 512 but the actual architectural maximum is 16, a substantial difference which might not be obvious to readers especially given the several different units used for specifying vector sizes in various contexts and the fact that it's often used via macros. In an effort to minimise surprises for users who might assume the value is the architectural maximum and use it to do things like size allocations add a comment noting the difference. Signed-off-by: Mark Brown --- arch/arm64/include/uapi/asm/sve_context.h | 4 ++++ 1 file changed, 4 insertions(+) --- base-commit: 54be6c6c5ae8e0d93a6c4641cb7528eb0b6ba478 change-id: 20240206-arm64-sve-vl-max-comment-64efa3f03625 Best regards, diff --git a/arch/arm64/include/uapi/asm/sve_context.h b/arch/arm64/include/uapi/asm/sve_context.h index 754ab751b523..59f283f373a6 100644 --- a/arch/arm64/include/uapi/asm/sve_context.h +++ b/arch/arm64/include/uapi/asm/sve_context.h @@ -13,6 +13,10 @@ #define __SVE_VQ_BYTES 16 /* number of bytes per quadword */ +/* + * Note that for future proofing __SVE_VQ_MAX is defined much larger + * than the actual architecture maximum of 16. + */ #define __SVE_VQ_MIN 1 #define __SVE_VQ_MAX 512