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 5F9E4225788 for ; Sun, 30 Aug 2026 01:50:31 +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=1788054631; cv=none; b=F6fcDYjWLjU0CGTekI7hQ+UdYSsTtcXd39WZvQnSHtVRnGTk8lkrTOzOlKLFodsD6NajygLst1tx4AITPjnIdPSgekfu2zWaFTh2QluDrcVcYukgfcDv0SHZticehPI6W8C/FiQoTZ63hItpcsdA7ZK5filj9Qff61ESGAC/lkg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788054631; c=relaxed/simple; bh=jTpk5SXBQIBLi5wPENuLfGKtp4AxzWkuAVdCJuaqOKw=; h=From:To:Subject:Date:Message-ID:In-Reply-To:References: Content-Type:MIME-Version; b=XwlVtlr4+m0R9xkHJJN+qjOKxhDrXzna1SEINn62sMHy6hIQNQC61NdXOxcuzsdd6UaDzqgL44ti8RQRoGmKuj96EIQatFHTgtDoRBaCDuXGNIqCMvPQJ11wzCef9kD0Q4L9D1cUNtK5BUPme/fnFdzyZxBI8oOxPicOI7XnEoA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=jHDI6anY; 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="jHDI6anY" Received: by smtp.kernel.org (Postfix) with ESMTPS id E3914C2BCFF for ; Sun, 30 Aug 2026 01:50:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1788054630; bh=jTpk5SXBQIBLi5wPENuLfGKtp4AxzWkuAVdCJuaqOKw=; h=From:To:Subject:Date:In-Reply-To:References:From; b=jHDI6anYWttRRSA/f9z+D9eBr8+QXBQlbMEasH3bbwXC+jgh551Iva+x9Uz1abbXC sXSJzSOyP8OmhZGP3zCc9yngB1/C1BxWza+ihB6qXBdCMAFQ3TkKWQf3a4TKMAkgFg QqbaeP5HTuFWASbE8Lpd7FAj9vA2g7nRkXkON1nzouGVMdMCkRs20cZ6tUZDJKKhlA IVrzbwPJMYo+ukjxcd6LJG8vLlsBTOn3jUCOsEsJwx68T10GGgb8Cj8dvd2DjOR++b nXSqQQFxfbQ5Bv/LQ6qwAUr0sMan6u0lJHJIlRANAN7o8k+nHci2WkPmy/BvYNTHgN xvwX740rMBffg== Received: by aws-us-west-2-korg-bugzilla-1.web.codeaurora.org (Postfix, from userid 48) id C99BBC53BC9; Sun, 30 Aug 2026 01:50:30 +0000 (UTC) From: bugzilla-daemon@kernel.org To: linux-usb@vger.kernel.org Subject: [Bug 221103] xhci_hcd: System lockup under CPU load during usbfs polling of USB devices on AMD platforms Date: Sun, 30 Aug 2026 01:50:30 +0000 X-Bugzilla-Reason: None X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: AssignedTo drivers_usb@kernel-bugs.kernel.org X-Bugzilla-Product: Drivers X-Bugzilla-Component: USB X-Bugzilla-Version: 2.5 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: voltara@gmail.com X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: drivers_usb@kernel-bugs.kernel.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: attachments.created 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: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 https://bugzilla.kernel.org/show_bug.cgi?id=3D221103 --- Comment #31 from Andrew Skalski (voltara@gmail.com) --- Created attachment 310754 --> https://bugzilla.kernel.org/attachment.cgi?id=3D310754&action=3Dedit patch that adds msleep(10) to xhci_resume The attached patch adds msleep(10) to xhci_resume. This small delay seems = to have stopped my machine from crashing in all cases (adb, plugging in device= s, cat /dev/bus/usb/*/*) By adding debug logging to drivers/usb/host/xhci.c, I found the line of code where the lockup appears to occur. Specifically, when this function is cal= led by xhci_resume(). static void xhci_set_cmd_ring_deq(struct xhci_hcd *xhci) { ... crcr =3D xhci_read_64(xhci, &xhci->op_regs->cmd_ring); // this line ... } --=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.=