From: Eric Biggers <ebiggers@kernel.org>
To: x86@kernel.org
Cc: linux-um@lists.infradead.org, linux-raid@vger.kernel.org,
linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org,
Christoph Hellwig <hch@lst.de>,
Andrew Morton <akpm@linux-foundation.org>,
Eric Biggers <ebiggers@kernel.org>
Subject: [PATCH 5/8] lib/crc: x86: Stop using cpu_has_xfeatures()
Date: Thu, 25 Jun 2026 21:37:28 -0700 [thread overview]
Message-ID: <20260626043731.319287-6-ebiggers@kernel.org> (raw)
In-Reply-To: <20260626043731.319287-1-ebiggers@kernel.org>
Checking both boot_cpu_has() and cpu_has_xfeatures() has never really
been needed in practice, and it's never been universally done (e.g.,
lib/raid/ omits cpu_has_xfeatures()). Nevertheless, both x86 and UML
now explicitly clear the AVX and AVX-512 flags if their xfeatures are
missing, which should remove any remaining doubts.
Thus, remove all the calls to cpu_has_xfeatures().
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
---
lib/crc/x86/crc-pclmul-template.h | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/lib/crc/x86/crc-pclmul-template.h b/lib/crc/x86/crc-pclmul-template.h
index 02744831c6fa..893119bb7c07 100644
--- a/lib/crc/x86/crc-pclmul-template.h
+++ b/lib/crc/x86/crc-pclmul-template.h
@@ -25,20 +25,18 @@ crc_t prefix##_vpclmul_avx512(crc_t crc, const u8 *p, size_t len, \
DEFINE_STATIC_CALL(prefix##_pclmul, prefix##_pclmul_sse)
static inline bool have_vpclmul(void)
{
return boot_cpu_has(X86_FEATURE_VPCLMULQDQ) &&
- boot_cpu_has(X86_FEATURE_AVX2) &&
- cpu_has_xfeatures(XFEATURE_MASK_YMM, NULL);
+ boot_cpu_has(X86_FEATURE_AVX2);
}
static inline bool have_avx512(void)
{
return boot_cpu_has(X86_FEATURE_AVX512BW) &&
boot_cpu_has(X86_FEATURE_AVX512VL) &&
- !boot_cpu_has(X86_FEATURE_PREFER_YMM) &&
- cpu_has_xfeatures(XFEATURE_MASK_AVX512, NULL);
+ !boot_cpu_has(X86_FEATURE_PREFER_YMM);
}
/*
* Call a [V]PCLMULQDQ optimized CRC function if the data length is at least 16
* bytes, the CPU has PCLMULQDQ support, and the current context may use SIMD.
--
2.54.0
next prev parent reply other threads:[~2026-06-26 4:39 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-06-26 4:37 [PATCH 0/8] x86: Remove cpu_has_xfeatures() and add AVX-512 xor_gen() Eric Biggers
2026-06-26 4:37 ` [PATCH 1/8] x86/fpu: Check for missing AVX and AVX-512 xstate bits Eric Biggers
2026-06-26 5:00 ` sashiko-bot
2026-06-26 5:39 ` Christoph Hellwig
2026-06-26 4:37 ` [PATCH 2/8] um: " Eric Biggers
2026-06-26 7:41 ` David Laight
2026-06-26 8:21 ` Anton Ivanov
2026-06-26 10:49 ` David Laight
2026-06-26 20:55 ` Eric Biggers
2026-06-26 21:33 ` David Laight
2026-06-26 4:37 ` [PATCH 3/8] crypto: x86 - Stop using cpu_has_xfeatures() Eric Biggers
2026-06-26 4:37 ` [PATCH 4/8] lib/crypto: x86: " Eric Biggers
2026-06-26 4:53 ` sashiko-bot
2026-06-26 4:37 ` Eric Biggers [this message]
2026-06-26 4:37 ` [PATCH 6/8] x86/fpu: Remove cpu_has_xfeatures() Eric Biggers
2026-06-26 4:37 ` [PATCH 7/8] lib/raid/xor: x86: Remove redundant X86_FEATURE_OSXSAVE check Eric Biggers
2026-06-26 4:51 ` sashiko-bot
2026-06-26 5:40 ` Christoph Hellwig
2026-06-26 4:37 ` [PATCH 8/8] lib/raid/xor: x86: Add AVX-512 optimized xor_gen() Eric Biggers
2026-06-26 5:47 ` Christoph Hellwig
2026-06-26 5:47 ` Christoph Hellwig
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