From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pg1-f175.google.com (mail-pg1-f175.google.com [209.85.215.175]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 01EC8346E55 for ; Thu, 16 Jul 2026 06:41:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.175 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784184074; cv=none; b=aeJwX92fNgX/avUZY/KaEryu2mNGm3XlnM+8YJsztPP9gEH9I70I374B2AW+LFWrfpY7v1+28sNlnMYziJV1NzrMkReNdF+MUa+1/70JOuWAoNr+fWorDpvqXa5TZpq20gbXY9fI0E07q4JAfqbUax2SIkBH2VcUVI9bRTOM6d8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784184074; c=relaxed/simple; bh=ARwBqNXy7iYAR/zvzCQFr6JDEhfZR9bP5dOWQAURFD4=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=WEwwdM+486jn+PH/StoRy2P539BFB0M0ie++uiW8mZ90P7NARuuGQ001D6kzJ/sHk0ZV6VJYWrj3KDrnWVOFUQCqwvIyTLKgb8BJVUoIOshoP/sjmLxs1I69y2R7FT23xLi9uoZGxLxb5Pwo3P+SavkA7FSP2sqczumwwYHiqdw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=mNKBabSz; arc=none smtp.client-ip=209.85.215.175 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="mNKBabSz" Received: by mail-pg1-f175.google.com with SMTP id 41be03b00d2f7-c9e7391839cso2693818a12.0 for ; Wed, 15 Jul 2026 23:41:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1784184072; x=1784788872; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to:content-type; bh=8J2PB70MWAXXQG95F609SxeXRC3aZLcryE0e4szEh2g=; b=mNKBabSzr7e6d9eYDXFsrOOIme6opLnCbMqdxVWsqFAZoqisYQzpmAP+aheZO+ojE9 8R6il7HTeF9hkN5QDo9Wlx+3QLYmefBW2zzwV3+LDVOxsM0xuk9Xi+G+B+VNXe1jQAwT dISrkmT334aKh39dqI2q2uvjwEc6CbOjjUiYJfrfOGY4YJDx+orRX6D7iFGiXAKMIxke aM28OOLNLB9ce5snzFG1SMLt9NZNHu3HTBYHXk5HNNxTCX99GpmuKLmHE07jtvONY4Hc QRvs+zWI53ojl1ZwE8RH0P/0TA8mDC8SHWnc85HF054MKQhLGqFs0zACvQqWS7kiCEyW 0QXg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1784184072; x=1784788872; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=8J2PB70MWAXXQG95F609SxeXRC3aZLcryE0e4szEh2g=; b=Rp2L9QJ90Qp+YXrvTMuLhiWIn7TNa162yby4W1QEyvZnSwcuGjMGtE6m1ADHM5WRdb a2A+3kiPxeetIVhPAygnS4BcUFXs6US24LoDenDSW77hIYXVJjNEjmq94XQ36lkNuVnW GkfUfcuVbgpzqQyCDbgqAJ+CAgvT/vRpl6feCuvQHwGf50YvZBFqx2NJ0fY5FzXHJqCr vTueM94F0Uolnf8futHoWMFKoAZf6i/fmvuSbM+md1LDYx4yMWosUfqr5s1d+1nDcLrv rEYschfhkYwG6m6VyPJu8MWwdYwu2oDpiUSYiCsjYmmRBDHE6Aqa2C18yBZX5ooUM9Vm A76Q== X-Forwarded-Encrypted: i=1; AHgh+RrXWhjWHvpDxlkGNUyhP9EoLdllXwXh8i7+/dr7cYxEd8FvPl0eqnl2Ngz/tGdx/Etxgd7ZlKz2XSpXSWU=@vger.kernel.org X-Gm-Message-State: AOJu0YwAHDpTONsstSAtrMs9yKL1RN+ZkILzUFuAbZTelO2X16YCECRX wGv2kkml4BqjwKHAWDiUuMGH/8Q24JVjBjR+iBGc8yJUp3ePGaSOmxqI X-Gm-Gg: AfdE7cksvBzK6sBJKOQvgQvPMQw2JFvAhQxi7i4t1x52sitt1SoATbFMWBX1PWmWULe o6tiLqSSMSftusQ0bD3pKwKolYGmHRK5D69jDl2THqz9HhzoD3skMpV6RmajLEg2Py3ovsYike6 MKmrHceXkB1iZ2RLdA7KwthEmN1RMDlLecnXCNZRElTNcJpD1bE/Hz5Dv/FXEXaIK4TWrxVAoUz /SH6U4DXbVE5LBlflin0flxz1Or3S1r8meJgPHxB54OuI40bzlMKnUCgZdi8KkuOaInGlauW/lF e2Gp/zrT+tuRlvxyi5VkdKwyEuDrJZ9kHfRhhA+ZD3gWnMjMABNA6wqUww/N/ZpsHzOJflmctRV E/fhm6GGjBBJw31AgJvB+Xw7kI37CEBzJAb5rluz3D7pVQvdf/33sUm4VlMeId892durzRoIWnU wwugn7wiGVRJiYhQo8uNGc X-Received: by 2002:a05:6a21:495:b0:3c0:9c1b:d0b5 with SMTP id adf61e73a8af0-3c1109f44ebmr22579230637.64.1784184072215; Wed, 15 Jul 2026 23:41:12 -0700 (PDT) Received: from cyh-System-Product-Name.. ([129.227.183.200]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-cb258eb856dsm1412425a12.6.2026.07.15.23.41.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Jul 2026 23:41:11 -0700 (PDT) From: yhchen312@gmail.com To: anup@brainfault.org Cc: atish.patra@linux.dev, pjw@kernel.org, palmer@dabbelt.com, aou@eecs.berkeley.edu, alex@ghiti.fr, bigeasy@linutronix.de, clrkwllms@kernel.org, rostedt@goodmis.org, kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, linux-rt-devel@lists.linux.dev, "Yuhang.chen" , Quan Zhou Subject: [PATCH] RISC-V: KVM: Use raw_spinlock for VMID update critical section Date: Thu, 16 Jul 2026 14:40:11 +0800 Message-Id: <20260716064011.2387501-1-yhchen312@gmail.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: "Yuhang.chen" The VMID update critical section performs an IPI broadcast via on_each_cpu_mask() on VMID version rollover, which must not be preempted under PREEMPT_RT. Convert vmid_lock to raw_spinlock_t and use plain raw_spin_lock()/raw_spin_unlock() (interrupts stay enabled, since on_each_cpu_mask() requires it). Assisted-by: YuanSheng:deepseek-v4-pro Co-developed-by: Quan Zhou Signed-off-by: Quan Zhou Signed-off-by: Yuhang.chen --- arch/riscv/kvm/vmid.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/riscv/kvm/vmid.c b/arch/riscv/kvm/vmid.c index c15bdb1dd8be..21c2b276b55d 100644 --- a/arch/riscv/kvm/vmid.c +++ b/arch/riscv/kvm/vmid.c @@ -21,7 +21,7 @@ static unsigned long vmid_version = 1; static unsigned long vmid_next; static unsigned long vmid_bits __ro_after_init; -static DEFINE_SPINLOCK(vmid_lock); +static DEFINE_RAW_SPINLOCK(vmid_lock); void __init kvm_riscv_gstage_vmid_detect(void) { @@ -78,14 +78,14 @@ void kvm_riscv_gstage_vmid_update(struct kvm_vcpu *vcpu) if (!kvm_riscv_gstage_vmid_ver_changed(vmid)) return; - spin_lock(&vmid_lock); + raw_spin_lock(&vmid_lock); /* * We need to re-check the vmid_version here to ensure that if * another vcpu already allocated a valid vmid for this vm. */ if (!kvm_riscv_gstage_vmid_ver_changed(vmid)) { - spin_unlock(&vmid_lock); + raw_spin_unlock(&vmid_lock); return; } @@ -117,7 +117,7 @@ void kvm_riscv_gstage_vmid_update(struct kvm_vcpu *vcpu) WRITE_ONCE(vmid->vmid_version, READ_ONCE(vmid_version)); - spin_unlock(&vmid_lock); + raw_spin_unlock(&vmid_lock); /* Request G-stage page table update for all VCPUs */ kvm_for_each_vcpu(i, v, vcpu->kvm) -- 2.34.1 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 54A73C44512 for ; Thu, 16 Jul 2026 06:41:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-Id:Date:Subject:Cc :To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=4b+10Zru7RLZhINyUKqK2rrXnSAQaXf/a5eXBcRrecA=; b=A1A3GZMaCO7U40 gVwhpe+QHW67EL8vtzg0eZGhviIXtD4jHofQhtgMrgGnlVTtlE9JQdwAyu3LllK6CFUtVouJazv7n OqBXAk4tLApcrOFGeFbRElRDEi7cj8AtsuH3AfIOTq469MCIdQYPYDFsbQMlIj80ESEz1MPzZRYcX 16WTnIehC3fYXw4BWRa7MyEJzXgqyXTX84A2qm1fuPewoDCQOi52H3OZ5YdZ374hradUNtaASAYF2 5xtFzNfYD5RE9jjST+DqGq1ioe3bISEk38zQH8P5Wl2ptel0OcjzW0hoNp5Dw7nlKti09M94sEd6H AQJwjHl4g8sV9reJ9d+Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wkFmW-0000000GYOA-0v2u; Thu, 16 Jul 2026 06:41:16 +0000 Received: from mail-pg1-x52d.google.com ([2607:f8b0:4864:20::52d]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wkFmT-0000000GYNL-2jYX for kvm-riscv@lists.infradead.org; Thu, 16 Jul 2026 06:41:15 +0000 Received: by mail-pg1-x52d.google.com with SMTP id 41be03b00d2f7-c99eaa1f020so2842327a12.2 for ; Wed, 15 Jul 2026 23:41:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1784184072; x=1784788872; darn=lists.infradead.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to:content-type; bh=8J2PB70MWAXXQG95F609SxeXRC3aZLcryE0e4szEh2g=; b=IAgshyo49FYaU59XoV3zgs0EBYtWcwhgQcndT92zxNjfKX5drkGYhKe24VDfAaaI5B WVKfTNjnb4vkAKfDU5mUx/WQ2t/+MSbhmWv+60TL6Q5oCmD1ycuGoE4QacYy9+J15TuC /d5WIBri2XhSNk5nFZhPYLXmPcCAF9sdpq0SIw0ATEVVPHkADXK7mH4MhBYsAF0pQYCF z8BiOodNJ4AG/cPsHRToayW3+JkPKzzF8TwtlEt3B6rXnwvX9SDZ8NU+4/5GX1ey7MXa wj+sue7bUX6eVhDA0puz0zdvsVUcFJHmSc1f0HNneYWudl2DaYYAbx4s6aEN//jcj5L4 rojQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1784184072; x=1784788872; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=8J2PB70MWAXXQG95F609SxeXRC3aZLcryE0e4szEh2g=; b=lYNcAsvJoxmbjyhT+AACRmn6oxBGNdG8+w8eGXTZHUPLacLe3W6B5eKCp+VJZGLf0S orf79NpENmMf/rqNtL7ta+5eZn4JZniVYmYA8WHWOEwIM7XyxpnQCLZjPXqO0sVgBnAS e8bgIuM0IQUIfb2WIn+tRIrB2xuq9awda+QHlq0eoEQ7TXFsDKXec2ck197YHnqQXVlT 8QX4T7U/uQ4DhrmX/FoTwCNntlKISTvfQO+NlKcC+jrFUn3cjhVCjaFoqCLfRAvC0Kpo xHWaMRsh/wpgpvP0gep6doEmW5yKZhHBZ1i/eBd3yDq9+KidNMRxYCvoeF8mOxGgAvLQ X/5Q== X-Forwarded-Encrypted: i=1; AHgh+RoVVumzTfNxvzQoUeNluzsOvZNW0TKyF9Q/E8JZb67zFP5U94lDhpLzMmWN+cYSHpuvmsVpcvJZEvM=@lists.infradead.org X-Gm-Message-State: AOJu0YxNqNtX9+PuwRispudqCVm+AuzYCpwvmFd1+YLbzFlRarNfG9HZ xXucIiv72BRD4iT79qCjx9FgL7755SiHkUJ6V0uTN/q5XUyQecWYRmYy X-Gm-Gg: AfdE7clLf3jAGE1X+QcMroYlADHtRtSUtpalp9SFyYqLhSsSvabIDymps6J/53oy00T gRONs64TlRXsgu7VP0Bx/yis0u/m5GpMgSX9QsYWnkbJgx/Tg4BredOYMjt+HD+XEfuVdIihXhi 3+pvXv/USQxWzt+hKNl5oediFTupTPBnLvWQkIBHDJxPdcl1CFEsG5fiTxv9+dc+yYqyUUN6L5Y tW+UPB5Nbx9RelOjM2lodnLgCAYreMDHSkpqwOWlYWzSoo6rubCB/TaHCYBe66I8ZasVOTOoHxY qLcI80zCkT9XIv3NBthzKAhn0ydYzDEB61lDjVSANs9Bi+hBm7eWfAsK9mBbASeWoBuDtgM9oh/ wor5uqOJx6v2cwD768Loxm4FS6VMFZUpn9xi8T9G3IJHdD3Ivdiwz9DUR1d9yGfgoPfXpvq6N9L elR6EFE7bHo/D4McrqERtW X-Received: by 2002:a05:6a21:495:b0:3c0:9c1b:d0b5 with SMTP id adf61e73a8af0-3c1109f44ebmr22579230637.64.1784184072215; Wed, 15 Jul 2026 23:41:12 -0700 (PDT) Received: from cyh-System-Product-Name.. ([129.227.183.200]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-cb258eb856dsm1412425a12.6.2026.07.15.23.41.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Jul 2026 23:41:11 -0700 (PDT) From: yhchen312@gmail.com To: anup@brainfault.org Cc: atish.patra@linux.dev, pjw@kernel.org, palmer@dabbelt.com, aou@eecs.berkeley.edu, alex@ghiti.fr, bigeasy@linutronix.de, clrkwllms@kernel.org, rostedt@goodmis.org, kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, linux-rt-devel@lists.linux.dev, "Yuhang.chen" , Quan Zhou Subject: [PATCH] RISC-V: KVM: Use raw_spinlock for VMID update critical section Date: Thu, 16 Jul 2026 14:40:11 +0800 Message-Id: <20260716064011.2387501-1-yhchen312@gmail.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260715_234113_698866_BC104DD7 X-CRM114-Status: GOOD ( 10.89 ) X-BeenThere: kvm-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kvm-riscv" Errors-To: kvm-riscv-bounces+kvm-riscv=archiver.kernel.org@lists.infradead.org From: "Yuhang.chen" The VMID update critical section performs an IPI broadcast via on_each_cpu_mask() on VMID version rollover, which must not be preempted under PREEMPT_RT. Convert vmid_lock to raw_spinlock_t and use plain raw_spin_lock()/raw_spin_unlock() (interrupts stay enabled, since on_each_cpu_mask() requires it). Assisted-by: YuanSheng:deepseek-v4-pro Co-developed-by: Quan Zhou Signed-off-by: Quan Zhou Signed-off-by: Yuhang.chen --- arch/riscv/kvm/vmid.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/riscv/kvm/vmid.c b/arch/riscv/kvm/vmid.c index c15bdb1dd8be..21c2b276b55d 100644 --- a/arch/riscv/kvm/vmid.c +++ b/arch/riscv/kvm/vmid.c @@ -21,7 +21,7 @@ static unsigned long vmid_version = 1; static unsigned long vmid_next; static unsigned long vmid_bits __ro_after_init; -static DEFINE_SPINLOCK(vmid_lock); +static DEFINE_RAW_SPINLOCK(vmid_lock); void __init kvm_riscv_gstage_vmid_detect(void) { @@ -78,14 +78,14 @@ void kvm_riscv_gstage_vmid_update(struct kvm_vcpu *vcpu) if (!kvm_riscv_gstage_vmid_ver_changed(vmid)) return; - spin_lock(&vmid_lock); + raw_spin_lock(&vmid_lock); /* * We need to re-check the vmid_version here to ensure that if * another vcpu already allocated a valid vmid for this vm. */ if (!kvm_riscv_gstage_vmid_ver_changed(vmid)) { - spin_unlock(&vmid_lock); + raw_spin_unlock(&vmid_lock); return; } @@ -117,7 +117,7 @@ void kvm_riscv_gstage_vmid_update(struct kvm_vcpu *vcpu) WRITE_ONCE(vmid->vmid_version, READ_ONCE(vmid_version)); - spin_unlock(&vmid_lock); + raw_spin_unlock(&vmid_lock); /* Request G-stage page table update for all VCPUs */ kvm_for_each_vcpu(i, v, vcpu->kvm) -- 2.34.1 -- kvm-riscv mailing list kvm-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kvm-riscv From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 4A757C44501 for ; Thu, 16 Jul 2026 06:41:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-Id:Date:Subject:Cc :To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=r6hjpsHcWAIDNG9I+m6xqDBkuE7oW2BYY94QN0Pj+Co=; b=016GjX9uVCzHxD 1Tm3Lrf2l5lEwzx+VOTvtJPEHDiv0nw0dBSI62XsazJ7OvmQ/5omaBNOap41qMp+W3J7k5n/AkGV2 TvyjRVdToJMV33UOXkWW1nwiw0Hxi1TeQTl88f1q2YdBC4b78wU4q/iaq/D8DRyEOs38amNCF73Iu emj/gY5dqDdmHAxzTeVNEPDi9LkazRNNfbxc1ykEPWXRWpbmg0LEwYPhqpo/eDkrYCkR2Y3tyChUI UrYUPxjS2H3XW4qEQ3hCwM41oyx/Qe4H5ah/v0dzPEeHNdoxI3uibwoClB9CpE+4+pPVrvZ7gETcl BFnmAUWULQ/LCAj9o4IA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wkFmW-0000000GYO6-0SAk; Thu, 16 Jul 2026 06:41:16 +0000 Received: from mail-pg1-x52e.google.com ([2607:f8b0:4864:20::52e]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wkFmT-0000000GYNK-2jEa for linux-riscv@lists.infradead.org; Thu, 16 Jul 2026 06:41:14 +0000 Received: by mail-pg1-x52e.google.com with SMTP id 41be03b00d2f7-c99eaa1f020so2842328a12.2 for ; Wed, 15 Jul 2026 23:41:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1784184072; x=1784788872; darn=lists.infradead.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to:content-type; bh=8J2PB70MWAXXQG95F609SxeXRC3aZLcryE0e4szEh2g=; b=IAgshyo49FYaU59XoV3zgs0EBYtWcwhgQcndT92zxNjfKX5drkGYhKe24VDfAaaI5B WVKfTNjnb4vkAKfDU5mUx/WQ2t/+MSbhmWv+60TL6Q5oCmD1ycuGoE4QacYy9+J15TuC /d5WIBri2XhSNk5nFZhPYLXmPcCAF9sdpq0SIw0ATEVVPHkADXK7mH4MhBYsAF0pQYCF z8BiOodNJ4AG/cPsHRToayW3+JkPKzzF8TwtlEt3B6rXnwvX9SDZ8NU+4/5GX1ey7MXa wj+sue7bUX6eVhDA0puz0zdvsVUcFJHmSc1f0HNneYWudl2DaYYAbx4s6aEN//jcj5L4 rojQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1784184072; x=1784788872; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=8J2PB70MWAXXQG95F609SxeXRC3aZLcryE0e4szEh2g=; b=qalCpczwK/4X+EZnnBr52QDIpGii8vDa/ldb2blE5uhB1SJ94zbUCUBfV3FL+AJfm1 mUHQ4tkDGVTJS758VnsaX1jbuQ4iDpIZXZQsBvLXn5Hbm+BTBeOvOq7Sagdd28truro5 FyUuxOnpJVtMtDkcY+s5Hpz1KkjFYE6wzC8ad7+xMivltdaeVaUVryCcWYVlBI2lD3/7 FuVJLFozUE8Dzf0Z4rtXSNy6qNwcW70kBscBeiKRWNijbp8ETBUxkGfXvofPQee0N9XG QYLv0+wbOnTswgsJ1GCP01Sp6cvQ7sCHbwaD0z4gfqfOEePCuw8ymZBiLZzSA9xr8IWT 6zzw== X-Forwarded-Encrypted: i=1; AHgh+RoH/aRlV47vCULJEAi+/tlFfHq4uhDOYNOfpJV+jXsDyMh4CbrmdyKRG6n0fo8ujXh6NIonxiPd9qlX9w==@lists.infradead.org X-Gm-Message-State: AOJu0YwuA1Sd0T1qMr5ME4UGo2gXV4kdd5j53ikA25eVdv/LED29CZk5 2t8NlwDEBHux3X+Suo9aIYAOzxvcOUYLwpplh1++p/IqFqBy+AxHM8wH X-Gm-Gg: AfdE7cmfqbrOfW1oLXuM31uA5CucMbizYWOqvYa+aoeYmihoq/V1gKespaJ1g1YkoQj h9+8qO+11F4ZFIO3q+xD6Y3WbrJmporJK/1xOttvbCQPjKP96zha/FKIfzAlbVlMYsvuGBYzXR+ aaggCJeH4jC2wdxghWDNplJ3ruygX5nsXOSV6yyB7fKSLLAJbu7mQMFBJSFh/mOg2cVGEbkGg/D zPJ/lSeVM1uyN/ae5OgncsQNbipnR03Qb0K3hiBgFXfs57V9l/xTu+QXKEkYtLVTQpueG2AVNCv twteRBw9PaVfeZ6eeTZKu+93jKddysfHsGYnzPxbGl8wJwhaW6F+VvE3HS/TpFuK3EbuZ7qMNrJ ed6chxaRGxNAf1WddiOZHbwrIclOY3+5KbbLr57sEer8QlgxyblNaOCArtl6REwqgO+h3+b/rLA RbRi5EZY1smtfin2cg2/4d X-Received: by 2002:a05:6a21:495:b0:3c0:9c1b:d0b5 with SMTP id adf61e73a8af0-3c1109f44ebmr22579230637.64.1784184072215; Wed, 15 Jul 2026 23:41:12 -0700 (PDT) Received: from cyh-System-Product-Name.. ([129.227.183.200]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-cb258eb856dsm1412425a12.6.2026.07.15.23.41.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Jul 2026 23:41:11 -0700 (PDT) From: yhchen312@gmail.com To: anup@brainfault.org Cc: atish.patra@linux.dev, pjw@kernel.org, palmer@dabbelt.com, aou@eecs.berkeley.edu, alex@ghiti.fr, bigeasy@linutronix.de, clrkwllms@kernel.org, rostedt@goodmis.org, kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, linux-rt-devel@lists.linux.dev, "Yuhang.chen" , Quan Zhou Subject: [PATCH] RISC-V: KVM: Use raw_spinlock for VMID update critical section Date: Thu, 16 Jul 2026 14:40:11 +0800 Message-Id: <20260716064011.2387501-1-yhchen312@gmail.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260715_234113_698828_D565DCED X-CRM114-Status: GOOD ( 10.89 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org From: "Yuhang.chen" The VMID update critical section performs an IPI broadcast via on_each_cpu_mask() on VMID version rollover, which must not be preempted under PREEMPT_RT. Convert vmid_lock to raw_spinlock_t and use plain raw_spin_lock()/raw_spin_unlock() (interrupts stay enabled, since on_each_cpu_mask() requires it). Assisted-by: YuanSheng:deepseek-v4-pro Co-developed-by: Quan Zhou Signed-off-by: Quan Zhou Signed-off-by: Yuhang.chen --- arch/riscv/kvm/vmid.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/riscv/kvm/vmid.c b/arch/riscv/kvm/vmid.c index c15bdb1dd8be..21c2b276b55d 100644 --- a/arch/riscv/kvm/vmid.c +++ b/arch/riscv/kvm/vmid.c @@ -21,7 +21,7 @@ static unsigned long vmid_version = 1; static unsigned long vmid_next; static unsigned long vmid_bits __ro_after_init; -static DEFINE_SPINLOCK(vmid_lock); +static DEFINE_RAW_SPINLOCK(vmid_lock); void __init kvm_riscv_gstage_vmid_detect(void) { @@ -78,14 +78,14 @@ void kvm_riscv_gstage_vmid_update(struct kvm_vcpu *vcpu) if (!kvm_riscv_gstage_vmid_ver_changed(vmid)) return; - spin_lock(&vmid_lock); + raw_spin_lock(&vmid_lock); /* * We need to re-check the vmid_version here to ensure that if * another vcpu already allocated a valid vmid for this vm. */ if (!kvm_riscv_gstage_vmid_ver_changed(vmid)) { - spin_unlock(&vmid_lock); + raw_spin_unlock(&vmid_lock); return; } @@ -117,7 +117,7 @@ void kvm_riscv_gstage_vmid_update(struct kvm_vcpu *vcpu) WRITE_ONCE(vmid->vmid_version, READ_ONCE(vmid_version)); - spin_unlock(&vmid_lock); + raw_spin_unlock(&vmid_lock); /* Request G-stage page table update for all VCPUs */ kvm_for_each_vcpu(i, v, vcpu->kvm) -- 2.34.1 _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv