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 398531581E5 for ; Wed, 10 Apr 2024 10:44:53 +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=1712745893; cv=none; b=UmXvXDwdAAqvWADX4mFQK7fZi04OF3DLUhcyXinp8Lt21qmG+hLJxFo37pgfNp4gQEK/5sf+zrH3tyF8tbSnMMZIL0E4GktaVEWnbLg3on8bGbsHwl6vW00WYl3Ia4CvmBTEp4wCBUnMwTXO6hRs0Qo8qg0/ELEUU3YSFBdR6TQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712745893; c=relaxed/simple; bh=E2qRccl6FePjXOJpIrk4XJsvl5r5/THJNaRGiYJ34JQ=; h=From:To:Subject:Date:Message-ID:In-Reply-To:References: Content-Type:MIME-Version; b=I5qejORyCBAjiYAMd6nu0iIcuM+GYTfvHe8DdoSyT8mPRcac/386+NEeIhxPLCeRt+nExvLQ0SmwiogTSZ1BCvKUkCD+vrI1oq9Nd/0oEZT6d4Loo67FMlzYp5V1kaIXog+jz1Q4U88HaWLzAOswFMmEYPU3PCBnG794c7fj670= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=G69cY/SA; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="G69cY/SA" Received: by smtp.kernel.org (Postfix) with ESMTPS id 14C70C433A6 for ; Wed, 10 Apr 2024 10:44:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1712745893; bh=E2qRccl6FePjXOJpIrk4XJsvl5r5/THJNaRGiYJ34JQ=; h=From:To:Subject:Date:In-Reply-To:References:From; b=G69cY/SAJ3Xn2MqAk6p60ueyouKSEn0Ybe8g1mpemxSojnATge+wA9dqhpzWUjglw eWI+diUI9iqK0lB5XvKr3DuYbi0TwSmso0cuuzKPXYRndjHwkillY8mgWOVGWVaWDt MUNR8op590WK+woM8Qd8Rs4pitB/FgaZFjd1/vzBOYXQwNfOCcK5PTqfYUapx43S5S sjQP3TZyWSd5wPsMclLm0yINZJ19Rd1YuwuJpl6k9J2s8TINtNdngnwL3vVybbIFIL qTIyJ5lRD3g/A/VRjwJOWt+/+oqkfjzbhSiFKD6CXF5yhroJYAy8n83tYiJPkryLOd p0WnuFVj87FzA== Received: by aws-us-west-2-korg-bugzilla-1.web.codeaurora.org (Postfix, from userid 48) id EDB72C53BDA; Wed, 10 Apr 2024 10:44:52 +0000 (UTC) From: bugzilla-daemon@kernel.org To: kvm@vger.kernel.org Subject: [Bug 218684] CPU soft lockups in KVM VMs on kernel 6.x after switching hypervisor from C8S to C9S Date: Wed, 10 Apr 2024 10:44:52 +0000 X-Bugzilla-Reason: None X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: AssignedTo virtualization_kvm@kernel-bugs.osdl.org X-Bugzilla-Product: Virtualization X-Bugzilla-Component: kvm X-Bugzilla-Version: unspecified X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: frantisek@sumsal.cz X-Bugzilla-Status: RESOLVED X-Bugzilla-Resolution: PATCH_ALREADY_AVAILABLE X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: virtualization_kvm@kernel-bugs.osdl.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugzilla.kernel.org/ Auto-Submitted: auto-generated Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 https://bugzilla.kernel.org/show_bug.cgi?id=3D218684 --- Comment #4 from Frantisek Sumsal (frantisek@sumsal.cz) --- (In reply to Sean Christopherson from comment #3) > Given that 6.7 is still broken, my money is on commit d02c357e5bfa ("KVM: > x86/mmu: Retry fault before acquiring mmu_lock if mapping is changing").= =20 > Ugh, which I neglected to mark for stable. >=20 > Note, if that's indeed what's to blame, there's also a bug in the kernel's > preemption model logic that is contributing to the problems. > https://lore.kernel.org/all/20240110214723.695930-1-seanjc@google.com You're absolutely right. I took the C9S kernel RPM (5.14.0-436), slapped d02c357e5bfa on top of it, and after running the same tests as in previous cases all the soft lockups seem to be magically gone. Thanks a lot! I'll run a couple more tests and if they pass I'll go ahead and sum this up= in a RHEL report, so the necessary patches make it to C9S/RHEL9. --=20 You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.=