From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id BF5FC412C1A for ; Wed, 16 Sep 2026 23:04:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789599898; cv=none; b=bXBzybf61xrjaG8DrBUUw5cOBCYKqGqMGgCshUMgLR+UcxWxjq+Qjq/kk0L9pF5u6felCYxdRgHurmXS+6Rnj65I9XdF3oAS0uU3if5/Jd/fTcr3G3x3ZSUjCWCx/ysjlh3n4cv8LE+B64E2IjQcjmbgn6YYMv3yrAEZZ1kTgCE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789599898; c=relaxed/simple; bh=wkNpSDNZfRTYlKzv+KDudj0npKw1I5FMQNwmEMqYQ0k=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=AByTXX/HDYBFl4oK9IXJGw4mR7ZPj+orA4YvJrsdhszQ8l7n0Ky+BlPsvYx5iADImR07UIc/+fi0/ZUPBHPM4ZkoeXeaxwp0e21Lk7TV4vu2xKvphuXv53MKEBaFlShE6I+OgmUdUEvhSQt2zHBBS8RerT5jkFzJweEblbLpgUc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=OKTwVo/A; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="OKTwVo/A" Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 654061476; Wed, 16 Sep 2026 16:04:51 -0700 (PDT) Received: from workstation-e142269.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 02F613F7B4; Wed, 16 Sep 2026 16:04:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1789599895; bh=wkNpSDNZfRTYlKzv+KDudj0npKw1I5FMQNwmEMqYQ0k=; h=From:To:Cc:Subject:Date:From; b=OKTwVo/AQtdupYUE7FDpC+F6hT5YJ8C57ltsT+Id1mdnhxzjsPryo26VDsUaJeZ/8 tnZokvPCEo8M4rz3l1d0MnAe+p1lRLygmQvfQ1KNs6pWQdalxTzGGt18yIS/0UWIqU bhIEYllbYnrKDdwak8rnkifXwsENxkBdO6ElIi0g= From: Wei-Lin Chang To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org Cc: Marc Zyngier , Oliver Upton , Fuad Tabba , Joey Gouly , Steffen Eiden , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon , Mark Rutland , Vincent Donnefort , Sebastian Ene , Itaru Kitayama , Wei-Lin Chang Subject: [PATCH v3 0/2] KVM: arm64: ptdump: Shadow ptdump fixes Date: Thu, 17 Sep 2026 00:03:35 +0100 Message-ID: <20260916230337.4162485-1-weilin.chang@arm.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Hi, This is v3 of fixing the sleep-in-atomic problem of the shadow ptdump. The approach taken this time is simply creating a file for each nested mmu. The ptdump files are created alongside the nested mmus in kvm_vcpu_init_nested(), in a sleepable context, and removed when the VM is destroyed (kvm_destroy_vm_debugfs(), before the nested mmus are freed in kvm_destroy_nested()). This allows us to store the kvm_s2_mmu pointers in the ptdump code, after Marc's nested mmu lifecycle fixes [1]. For the shadow ptdump, for valid nested mmus the first line will show the nested context's VTTBR and VTCR values, and whether s2 is enabled or not. The ptdump then follows. The first patch fixes mmu->pgt accesses after the VM MMU teardown in ptdump.c, the second patch switches from per nested context ptdumps to per nested mmu ptdumps. Tested with CONFIG_PROVE_LOCKING, CONFIG_DEBUG_ATOMIC_SLEEP, and CONFIG_KASAN. Series based on kvmarm/fixes. * Changes from v2 [2]: - Changed from creating a file that contains all nested mmus to creating one file for each nested mmu. Thanks! [1]: https://lore.kernel.org/kvmarm/20260911162203.1919330-1-maz@kernel.org/ [2]: https://lore.kernel.org/kvmarm/20260630121005.1130996-1-weilin.chang@arm.com/ Wei-Lin Chang (2): KVM: arm64: ptdump: Check the page tables aren't freed when accessing KVM: arm64: ptdump: Fix shadow ptdump sleep-in-atomic-context problem arch/arm64/include/asm/kvm_host.h | 4 -- arch/arm64/include/asm/kvm_mmu.h | 6 +-- arch/arm64/kvm/nested.c | 9 ++-- arch/arm64/kvm/ptdump.c | 75 ++++++++++++++++++++----------- 4 files changed, 54 insertions(+), 40 deletions(-) -- 2.43.0