From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-yb1-f202.google.com (mail-yb1-f202.google.com [209.85.219.202]) (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 36D1E20E016 for ; Tue, 5 Nov 2024 19:34:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.219.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730835283; cv=none; b=JlijsHzgxBsV6j0QdgA23vMZ+5ThxXd8PHQPrL8ux6dbBmH35KI1ZSVTP4dz8CfcPI9mg0hvW8ujmmKyLBOxk4fdWr/7xZle0HJoGErES1wlHRy1kD+BPUCpcbl7KFHTjRbtRB88d1ZBr/Sz96x3V/u166Q8je7kNb0c9jTO0L0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730835283; c=relaxed/simple; bh=xPd4i6jpgEFj3QDbxccFoSZ95IE5WTJsPwiUZwvNonU=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=uocHqkagKi/4GAh8axmXpEhAOd4rUekDZqgPifR4t/kVNDCz26qSsACRsKP06Xr7L+lx3rw2su9vqJ0OE2JP/eL8B1t7RH9Jl2JF5rptZT72IGzQU+N7Wy4pvCBgxQcqrvv5t/3JLY97BoslEYapWAs/3r7qMbcNVC/+Sp4Tnw4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--jingzhangos.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=P5v0Y3dl; arc=none smtp.client-ip=209.85.219.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--jingzhangos.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="P5v0Y3dl" Received: by mail-yb1-f202.google.com with SMTP id 3f1490d57ef6-e291ac8dcf3so9451230276.3 for ; Tue, 05 Nov 2024 11:34:42 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1730835281; x=1731440081; darn=lists.linux.dev; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=8rG28HMeFmKNz149Y+Vw5VAUYNp3YmfGstywpzoeBNY=; b=P5v0Y3dlhfyGUJMg/nQtN0QTFplN2rSGuhGoML3IZL4MiMR4eVKiqsoJ3wsMq4BxWP +Vp3fcVl+HbMPsazEXB70+4TD2hqV0HVqQUPQSn1jMtiwNPhJ1RPihfxJghTgW5Q7yHZ aaYeqsoV1SdzFaVNeqKRqFicXANZNcByhBGLIsKqvy3tnu9LOag1DZGnQpBFulYCqfUi esLN7gPNqKnNYgfzPLNLPj9UJ/gq+mV73ajBiE6jm0Hq52Pw7WHS6qwbdxfDNpSv09IJ MiCPIOSipUjLwxKZlb0mwNn7+E5SXu2sZlTNJiiDEI0sy04dAzaDnyAlGti7ecXDyLuW QtFA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1730835281; x=1731440081; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=8rG28HMeFmKNz149Y+Vw5VAUYNp3YmfGstywpzoeBNY=; b=dkZqw5QZpKckXa/qpLn3AL3nzbZw/wiCTB39EFEKYq3tpZON7JC7MuDfwWWEhlLNh/ VW8nHhCYKbe61bsq+kCiezLN8Hd+qAQ8lN+z3wnm8pe0XUhA1aSKHNExaWWmk0x7ZUI4 VC+xCcXsHHf9nWCPq2JLV3R4e+UIXCaD9fGXmdl9IEdHnOsVd+kXuhxO6v0p1Apqsxkq N3ew57blddU4+qtTZm0YAZZE3R9mof/GgYj9RU2beDIvBqaEzEEUAC2qmHZ8vRa7U/M9 Fav9w/zyhtprcz8Gv7JxBn9MlRPoPaBxJJ6VvI4x+27LiB3z9degXAx6meaLawv0P+R7 gSbw== X-Forwarded-Encrypted: i=1; AJvYcCURti4F8nohX01u7Z9aLQLYJWfbUjXIlwD8I9SPSa4ohgf8gTXL+Zc+cTJUPP65NkUd0jYRhAI=@lists.linux.dev X-Gm-Message-State: AOJu0Yy+XtlJKRDm0TynEXwDaPsYjStNtSdre4Z9O+eMz+7hWEvULhLj gDB8OXeVeLqCJHIPhcJOcupzmhicU0RlglsHoXHoq9SQIqj3wSPIRTl0TJ/A5ER63OZxk5Pa2ce 3vzPXVziZ8c4OPRMb/qeD3g== X-Google-Smtp-Source: AGHT+IHSwjlYAEmxZvE3K18uqtu/bNQVHl4DA7qztn64qZnoHG833wnp2QKrs1chSkfAHMYdTQ7wPLIAKTndfwX+xQ== X-Received: from jgzg.c.googlers.com ([fda3:e722:ac3:cc00:36:e7b8:ac13:c96f]) (user=jingzhangos job=sendgmr) by 2002:a25:d616:0:b0:e29:76b7:ed37 with SMTP id 3f1490d57ef6-e3302669387mr18225276.9.1730835281208; Tue, 05 Nov 2024 11:34:41 -0800 (PST) Date: Tue, 5 Nov 2024 11:34:22 -0800 In-Reply-To: <20241105193422.1094875-1-jingzhangos@google.com> Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20241105193422.1094875-1-jingzhangos@google.com> X-Mailer: git-send-email 2.47.0.277.g8800431eea-goog Message-ID: <20241105193422.1094875-5-jingzhangos@google.com> Subject: [PATCH v1 4/4] KVM: arm64: vgic-its: Utilize the dummy entry in ITS tables restoring From: Jing Zhang To: KVM , KVMARM , ARMLinux , Marc Zyngier , Oliver Upton , Joey Gouly , Zenghui Yu , Suzuki K Poulose Cc: Paolo Bonzini , Andre Przywara , Colton Lewis , Raghavendra Rao Ananta , Jing Zhang Content-Type: text/plain; charset="UTF-8" Now, the first entry in tables is either a valid DTE/ITE or a dummy entry pointing to the first valid DTE/ITE. Revise the DTE/ITE restore process to utilize the dummy entry to avoid unnecessary (erroneous) entry scanning. This is not supposed to break the ITS table ABI REV0. Signed-off-by: Jing Zhang --- arch/arm64/kvm/vgic/vgic-its.c | 46 ++++++++++++++++++++++++++-------- 1 file changed, 35 insertions(+), 11 deletions(-) diff --git a/arch/arm64/kvm/vgic/vgic-its.c b/arch/arm64/kvm/vgic/vgic-its.c index 867cc5d3521d..e07939613f5c 100644 --- a/arch/arm64/kvm/vgic/vgic-its.c +++ b/arch/arm64/kvm/vgic/vgic-its.c @@ -2129,23 +2129,30 @@ static int vgic_its_restore_ite(struct vgic_its *its, u32 event_id, u32 coll_id, lpi_id; struct its_ite *ite; u32 offset; + u32 magic; val = *p; val = le64_to_cpu(val); - coll_id = val & KVM_ITS_ITE_ICID_MASK; lpi_id = (val & KVM_ITS_ITE_PINTID_MASK) >> KVM_ITS_ITE_PINTID_SHIFT; - if (!lpi_id) - return event_id + 1; /* invalid entry, no choice but to scan next entry */ + offset = val >> KVM_ITS_ITE_NEXT_SHIFT; + if (event_id + offset >= BIT_ULL(dev->num_eventid_bits)) + return -EINVAL; + + if (!lpi_id) { + magic = (val & KVM_ITS_ENTRY_DUMMY_MASK) >> KVM_ITS_ENTRY_DUMMY_SHIFT; + if (magic != KVM_ITS_ENTRY_DUMMY_MAGIC) + offset = 1; + + return event_id + offset; + } if (lpi_id < VGIC_MIN_LPI) return -EINVAL; - offset = val >> KVM_ITS_ITE_NEXT_SHIFT; - if (event_id + offset >= BIT_ULL(dev->num_eventid_bits)) - return -EINVAL; + coll_id = val & KVM_ITS_ITE_ICID_MASK; collection = find_collection(its, coll_id); if (!collection) @@ -2303,17 +2310,30 @@ static int vgic_its_restore_dte(struct vgic_its *its, u32 id, u64 entry = *(u64 *)ptr; bool valid; u32 offset; + u32 magic; int ret; entry = le64_to_cpu(entry); valid = entry >> KVM_ITS_DTE_VALID_SHIFT; - num_eventid_bits = (entry & KVM_ITS_DTE_SIZE_MASK) + 1; - itt_addr = ((entry & KVM_ITS_DTE_ITTADDR_MASK) - >> KVM_ITS_DTE_ITTADDR_SHIFT) << 8; - if (!valid) - return id + 1; + /* + * Since we created a dummy head entry for the DTE static linked list in + * the table if necessary, no need to scan to find the list head. + * But if the saved table was done without dummy entry support, we still + * have to scan one by one. + */ + if (!valid) { + magic = (entry & KVM_ITS_ENTRY_DUMMY_MASK) >> + KVM_ITS_ENTRY_DUMMY_SHIFT; + if (magic != KVM_ITS_ENTRY_DUMMY_MAGIC) + offset = 1; + else + offset = (entry & KVM_ITS_DTE_DUMMY_NEXT_MASK) >> + KVM_ITS_DTE_DUMMY_NEXT_SHIFT; + + return id + offset; + } /* dte entry is valid */ offset = (entry & KVM_ITS_DTE_NEXT_MASK) >> KVM_ITS_DTE_NEXT_SHIFT; @@ -2321,6 +2341,10 @@ static int vgic_its_restore_dte(struct vgic_its *its, u32 id, if (!vgic_its_check_id(its, baser, id, NULL)) return -EINVAL; + num_eventid_bits = (entry & KVM_ITS_DTE_SIZE_MASK) + 1; + itt_addr = ((entry & KVM_ITS_DTE_ITTADDR_MASK) + >> KVM_ITS_DTE_ITTADDR_SHIFT) << 8; + dev = vgic_its_alloc_device(its, id, itt_addr, num_eventid_bits); if (IS_ERR(dev)) return PTR_ERR(dev); -- 2.47.0.199.ga7371fff76-goog