From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 26F421E5206; Mon, 23 Jun 2025 21:48:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750715339; cv=none; b=sVZ5YNDOGjc1ppYN4k/LwpQbv1Jomvkvlc4bzphIoFNk2VpPJTJY3Ip2y7zQw+29XrOwycQEpDtHSJi0GkBScFNjPEs55RLKAJ4N66staaiCHdmzeJ5kLAGFfpbTY0ugLyVR7vBmVjdUS+ZN9xbg8LqARdLx+1zcimSxhbFW7qA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750715339; c=relaxed/simple; bh=bXxqvV/lcPiktTBWE8bZ9qDFnF2yS3hoFXlTRAJqMI0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ox/EOevNiZ8eRZuQ6Z/wE1hXNriadU3OEWL4cUOpEnmCqKnttPY46scytK358qZ2cRDFkoo3c0CfLgao7kZiRa8H675qyoEHQBoaHIxU81WMJ2XHcwOYTnHoV1PW3SPYfuR6dZOThAVYkv6XkAV/NV/vqpA24A+tQFPs8EYBgdc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=QqmUvtjR; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="QqmUvtjR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B38C9C4CEEA; Mon, 23 Jun 2025 21:48:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1750715339; bh=bXxqvV/lcPiktTBWE8bZ9qDFnF2yS3hoFXlTRAJqMI0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QqmUvtjRK2fpKU/4tG5tT8idH8OkSckhhndSP45j2Q4kniNBQKBnajNextnkZYqVl 9LMpaIpDClkIr0kEm+gSLbtcZDItWH8IpHI92T45NbcQu5gBEDlhJ1OUHHSPOQByZo U5XerCZlc41nFYY+vy7TP1Br422rQOvsRWsEHsFA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yanteng Si , WANG Rui , Huacai Chen Subject: [PATCH 6.15 452/592] LoongArch: Avoid using $r0/$r1 as "mask" for csrxchg Date: Mon, 23 Jun 2025 15:06:50 +0200 Message-ID: <20250623130711.181150043@linuxfoundation.org> X-Mailer: git-send-email 2.50.0 In-Reply-To: <20250623130700.210182694@linuxfoundation.org> References: <20250623130700.210182694@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Huacai Chen commit 52c22661c79a7b6af7fad9f77200738fc6c51878 upstream. When building kernel with LLVM there are occasionally such errors: In file included from ./include/linux/spinlock.h:59: In file included from ./include/linux/irqflags.h:17: arch/loongarch/include/asm/irqflags.h:38:3: error: must not be $r0 or $r1 38 | "csrxchg %[val], %[mask], %[reg]\n\t" | ^ :1:16: note: instantiated into assembly here 1 | csrxchg $a1, $ra, 0 | ^ To prevent the compiler from allocating $r0 or $r1 for the "mask" of the csrxchg instruction, the 'q' constraint must be used but Clang < 21 does not support it. So force to use $t0 in the inline asm, in order to avoid using $r0/$r1 while keeping the backward compatibility. Cc: stable@vger.kernel.org Link: https://github.com/llvm/llvm-project/pull/141037 Reviewed-by: Yanteng Si Suggested-by: WANG Rui Signed-off-by: Huacai Chen Signed-off-by: Greg Kroah-Hartman --- arch/loongarch/include/asm/irqflags.h | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) --- a/arch/loongarch/include/asm/irqflags.h +++ b/arch/loongarch/include/asm/irqflags.h @@ -14,40 +14,48 @@ static inline void arch_local_irq_enable(void) { u32 flags = CSR_CRMD_IE; + register u32 mask asm("t0") = CSR_CRMD_IE; + __asm__ __volatile__( "csrxchg %[val], %[mask], %[reg]\n\t" : [val] "+r" (flags) - : [mask] "r" (CSR_CRMD_IE), [reg] "i" (LOONGARCH_CSR_CRMD) + : [mask] "r" (mask), [reg] "i" (LOONGARCH_CSR_CRMD) : "memory"); } static inline void arch_local_irq_disable(void) { u32 flags = 0; + register u32 mask asm("t0") = CSR_CRMD_IE; + __asm__ __volatile__( "csrxchg %[val], %[mask], %[reg]\n\t" : [val] "+r" (flags) - : [mask] "r" (CSR_CRMD_IE), [reg] "i" (LOONGARCH_CSR_CRMD) + : [mask] "r" (mask), [reg] "i" (LOONGARCH_CSR_CRMD) : "memory"); } static inline unsigned long arch_local_irq_save(void) { u32 flags = 0; + register u32 mask asm("t0") = CSR_CRMD_IE; + __asm__ __volatile__( "csrxchg %[val], %[mask], %[reg]\n\t" : [val] "+r" (flags) - : [mask] "r" (CSR_CRMD_IE), [reg] "i" (LOONGARCH_CSR_CRMD) + : [mask] "r" (mask), [reg] "i" (LOONGARCH_CSR_CRMD) : "memory"); return flags; } static inline void arch_local_irq_restore(unsigned long flags) { + register u32 mask asm("t0") = CSR_CRMD_IE; + __asm__ __volatile__( "csrxchg %[val], %[mask], %[reg]\n\t" : [val] "+r" (flags) - : [mask] "r" (CSR_CRMD_IE), [reg] "i" (LOONGARCH_CSR_CRMD) + : [mask] "r" (mask), [reg] "i" (LOONGARCH_CSR_CRMD) : "memory"); }