From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 CE2E2384CD6 for ; Fri, 12 Jun 2026 14:41:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781275314; cv=none; b=OwVW/0M0O38NHHcrfxZRQGW5N+rPdX5ericrW29Rq73gL/AF4YyJ4z7Ozl6QmT91+pURnGKpdyzp/2pT4H1mbXZymOsGtUAer4lbht8JZrzAkbQRa9ZnFlZzuQqSmEuogIeI+OgnnCbbmvuydGIEUtV++jVgGGn7hcco6rDO2dU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781275314; c=relaxed/simple; bh=6iZkZgESgMQX/QZFVJDemaFY12GIEqJSn/lpeUYNKnc=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=IbWAxg0X+G/tEBeKp+lbwZMVWmllLMQwgGmrD7+kjz/pcYvWjUQu+9G3VXmnM4Z0jrZb0Zq1/e9mm3GKzIxkTkbilEeTxHyW8V70clqv4qHxo8297UmMhn7LWQs253V4qY2VdcD2hIipiz1+k14v88y6eKB0L7loHLEhdydmON4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=M+IrCART; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="M+IrCART" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4907E1F000E9; Fri, 12 Jun 2026 14:41:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1781275313; bh=IRPrI3yBAc/IgtOws2/bqKrXNJ/HJeBHmVWeQD6ll3s=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=M+IrCARTi3AxanZ0ACZm8WFEVcXCO33sgCa9oIpMzmogSjtZBz2Sq1njOHk6kVNFA cb+MMERu1Dw3bsbWfm8r0PxEdgZChmPEqwcPJ58RynFroIlQpvXlKxcHJXi8fo7s4t VkrRpuaXZ9GxEr3OfP1ArRkNBKOdqMB1L3fNA4t87sRFsdlwhSBEDF3CM08BdZG/BG DMTwHhv2SDl2u1Xcw8NZD++Q5Ur7vxRIZLlVEPe/0TaZR0KupnAmnqRSmriPnqXrJC 9uhHLr85ea4CGBkMcf7I7bQJ6mEGBKOjcDIakBNiLrIBUIMBGUz10TYkWVT4uM8TGU 9ACV1Yd6VHTJw== From: sashiko-bot@kernel.org Subject: Re: [PATCH v9] PCI: Add device-specific reset for Qualcomm devices Reply-To: sashiko-reviews@lists.linux.dev To: "Jose Ignacio Tornos Martinez" Cc: linux-pci@vger.kernel.org In-Reply-To: <20260612142638.1243895-1-jtornosm@redhat.com> References: <20260612142638.1243895-1-jtornosm@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Fri, 12 Jun 2026 14:41:52 +0000 Message-Id: <20260612144153.4907E1F000E9@smtp.kernel.org> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: > Some Qualcomm PCIe devices (WCN6855/WCN7850 WiFi cards, SDX62/SDX65 modem= s) > lack working reset methods for VFIO passthrough scenarios. These devices > have no FLR capability, advertise NoSoftRst+ (blocking PM reset), and have > broken bus reset. >=20 > The problem manifests in VFIO passthrough scenarios: >=20 > - WCN6855 WiFi card (17cb:1103): Normal VM operation works fine, including > clean shutdown/reboot. However, when the VM terminates uncleanly > (crash, force-off), VFIO attempts to reset the device before it can > be assigned to another VM. Without a working reset method, the device > remains in an undefined state, preventing reuse. >=20 > - WCN7850 WiFi card (17cb:1107): Same behavior as WCN6855. >=20 > - SDX62/SDX65 5G modems (17cb:0308): Never successfully initialize even > on first VM assignment without proper reset capability. >=20 > Add device-specific reset entries for these Qualcomm devices using D3hot > power cycling. Testing shows that despite advertising NoSoftRst+, D3hot > transition provides sufficient reset for VFIO reuse, particularly after > unexpected VM termination. While not a complete reset (BARs preserved), > it provides the only viable reset mechanism for these devices. >=20 > Testing was performed on desktop platforms with M.2 WiFi and modem cards > using M.2-to-PCIe adapters, including extensive force-reset cycling to > verify stability. >=20 > Signed-off-by: Jose Ignacio Tornos Martinez Sashiko has reviewed this patch and found no issues. It looks great! --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260612142638.1243= 895-1-jtornosm@redhat.com?part=3D1