From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1BA20C5321D for ; Tue, 27 Aug 2024 00:02:16 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 3BB5E6B0095; Mon, 26 Aug 2024 20:02:16 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 36BB26B009A; Mon, 26 Aug 2024 20:02:16 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 20C646B009C; Mon, 26 Aug 2024 20:02:16 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 02AD26B0095 for ; Mon, 26 Aug 2024 20:02:15 -0400 (EDT) Received: from smtpin08.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 2759840BF1 for ; Tue, 27 Aug 2024 00:02:15 +0000 (UTC) X-FDA: 82496073030.08.7F4C126 Received: from mail-wm1-f46.google.com (mail-wm1-f46.google.com [209.85.128.46]) by imf01.hostedemail.com (Postfix) with ESMTP id 591494001B for ; Tue, 27 Aug 2024 00:02:13 +0000 (UTC) Authentication-Results: imf01.hostedemail.com; dkim=pass header.d=gmail.com header.s=20230601 header.b=lFEl9vrA; spf=pass (imf01.hostedemail.com: domain of andreyknvl@gmail.com designates 209.85.128.46 as permitted sender) smtp.mailfrom=andreyknvl@gmail.com; dmarc=pass (policy=none) header.from=gmail.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1724716890; a=rsa-sha256; cv=none; b=rpHm5A2AfCQU2ULByWp6DJfqWUmFBV7TrMgNNsQN66MxvEhLitbkqVySzFOpeoHiO9u57q hazWT5Phd9UKphkwypCNF4znnHxiiL67MqylqeT1DNZ/bCFtKF6fdlXruoXBBkeuD0dP0Z Sh9cdl23ZeOUv8SIFvA9NKCcWNLxE4g= ARC-Authentication-Results: i=1; imf01.hostedemail.com; dkim=pass header.d=gmail.com header.s=20230601 header.b=lFEl9vrA; spf=pass (imf01.hostedemail.com: domain of andreyknvl@gmail.com designates 209.85.128.46 as permitted sender) smtp.mailfrom=andreyknvl@gmail.com; dmarc=pass (policy=none) header.from=gmail.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1724716890; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=3Lu2qvntF0LW0D6rPDpqRDqugVpTuyFFhTjrSXWCWNE=; b=3kogOb7V4x6pC0dUZVpBMh+HwWDKL79riFtg40LaUFnMYhbYa8S8Ew33Hf1BJ/no9s5rfW oQmjm8FQT/0Pcz5L+nq7qWOQc5lWPig0fg3VnIUL3/je0NcqURI10azHyZ7H6fh3By4aoW uCIj+tL1cvkXhCrLfAQmRyDnvrXUQ3U= Received: by mail-wm1-f46.google.com with SMTP id 5b1f17b1804b1-4281ca54fd3so42279175e9.2 for ; Mon, 26 Aug 2024 17:02:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1724716932; x=1725321732; darn=kvack.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=3Lu2qvntF0LW0D6rPDpqRDqugVpTuyFFhTjrSXWCWNE=; b=lFEl9vrAiFLhRMc6i7IEjVhnxhFtLkqwZdeg5uGSFrYu1aIAWdA1JMddeSJOarGbT9 5jsZH4S/wNK0n+6UYTr3/aajDrjkd3GePbDIjP84M4WD3FWjpkrSvhzhu4P8YaSrWbZM NiRiLCUAr5ja0DbW3VvOVTVNk4E/4BNuPeSjva9hUyJ+R/vRm4OALf4rElVRdbNvev6w FLSE9cCWnf5a007f9GvCA2KX/WhtoWKg96hPoXNWz2uXihXCQnw8FW/PEDS/oYd3F3to 0f60R475UrQC3slpqetfronAUDP4TLGYyRS32WCar+Ng7aidiwazpSrjTx4jaSIUlwGF Oe2g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1724716932; x=1725321732; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=3Lu2qvntF0LW0D6rPDpqRDqugVpTuyFFhTjrSXWCWNE=; b=c+TFmEP6w8z9gFHP4F0Xax+tvlSdnJhahNdgM8pybouDJWYUC496Xnasb7ObJpkd1K b/NtUVbli7WdAi1gZa25SnJ2oWnUCTl/1ZBbk5QesnCkq9Ary23NJ6Hgac5BlFE+Z07g Z1Tuxg/66BJEmSJjAnCa4OIPmnd9AbHiNkRKsabKn5JQ8fx7ipY2OjE7drPM4Wadz34G X8cMK3Zf7ev8pGAzlMBopSGerPK94kJfy+F2Fv03R6TY5z39QrqEtEBJ5xBAe8xjXYiN bAJnAOIIJGyq7ODjGnVLO1n4ieQuoHnLz/iJfqGxd9rJKi957DfpfR3SIAqb+NQhoe05 0x+Q== X-Forwarded-Encrypted: i=1; AJvYcCVXRzsYX35pneus61weTXgNBsbvPSBU8x6TAhymt1anlOf9OCl3+wGeAZdE623anL9FIVFr342BUQ==@kvack.org X-Gm-Message-State: AOJu0YxlnZ+8PesO7VTX0C5B6gU82iOSprLdcFaDDMZTkYxQFzTecJtI nPz0ZXfY6LcxS267I+DzH+xI0VtNB+Q/QqVVd3ThslM1XHOFS4TPzk6SPLDsTdbvk0keAronzhv ngwBM/LQLauwqur/yDWj8pljtwso= X-Google-Smtp-Source: AGHT+IGAM3TFs9NXhoHtmE3Cku2gMbd6wYRStVxQerrS1NZ8Nv7gH9pabCN8b2jcCBPPxX3JLq4ChV+hMWDv41wP16A= X-Received: by 2002:a05:600c:5250:b0:425:7884:6b29 with SMTP id 5b1f17b1804b1-42b9adf038dmr5996955e9.19.1724716931386; Mon, 26 Aug 2024 17:02:11 -0700 (PDT) MIME-Version: 1.0 References: <20240729022316.92219-1-andrey.konovalov@linux.dev> In-Reply-To: <20240729022316.92219-1-andrey.konovalov@linux.dev> From: Andrey Konovalov Date: Tue, 27 Aug 2024 02:02:00 +0200 Message-ID: Subject: Re: [PATCH] usb: gadget: dummy_hcd: execute hrtimer callback in softirq context To: Greg Kroah-Hartman Cc: Alan Stern , Marcello Sylvester Bauer , Dmitry Vyukov , Aleksandr Nogikh , Marco Elver , Alexander Potapenko , kasan-dev@googlegroups.com, Andrew Morton , linux-mm@kvack.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, syzbot+2388cdaeb6b10f0c13ac@syzkaller.appspotmail.com, syzbot+17ca2339e34a1d863aad@syzkaller.appspotmail.com, stable@vger.kernel.org, andrey.konovalov@linux.dev Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Stat-Signature: iosb8rqoex53qqubd9b7afffw1584n6w X-Rspamd-Queue-Id: 591494001B X-Rspam-User: X-Rspamd-Server: rspam10 X-HE-Tag: 1724716933-51826 X-HE-Meta: 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 /9VKiCjE +x+lDkoxdVFvHur8Icv1sc1DRHRiyHk1Cru4jowqbXi7c1s3sEBipa5lsEiC5t9GQwv3MNNT6f7kbAQNMIE5mEbTdcvvZVvxKNqxmykC5/dKAOll/Y8qD3+fkp+OBc0oBCzRxjv6btrynPUhqeUjlOKecQChPSEsb+AHOCXhAKElrOXeKVlwdusP0j/sFBEWsEi908R64RxSFsdro5FEqBdseyZ5C3NwU6kINUkfz1wDFrmIk9faHqJnVUrxzZsFiXFUh8wBIpTgfeiTeNi01e6AIMVpV6gSgf4cfIhmOVbjjjrSnUlh9sGpsN4Zobgi9fEdXW4A5wkbB3rk/PqULQ7arn1zlffY1o5kAop+ibTf0WgqHNcXgXClis8r06g1oZsaB3UGA3DJV/wzifrmNtzxzgvnR8UJjEgfC5uaxorjJNO70qsEuz4EuE4lWaVA/O9pnXJ+wAmHKbOU+del1bLgBtmEmZgMtLtgeKM03anD8rFmCeeHfm2DwDvz56A4fOKGnAXxxmOvyCNO/4rS47pJZFwdDNd1twvGaQ10yqJyobYIdjoJu3pT12NAEGq7RBLne3EIvx2Suln0qNycOjATwsZGNnLGxT/V8aaT/XcMjNflhcWfja1+HqJ2ysatuk6VP6++plVyPSo2M4MTTmFeuww== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, Jul 29, 2024 at 4:23=E2=80=AFAM wrote: > > From: Andrey Konovalov > > Commit a7f3813e589f ("usb: gadget: dummy_hcd: Switch to hrtimer transfer > scheduler") switched dummy_hcd to use hrtimer and made the timer's > callback be executed in the hardirq context. > > With that change, __usb_hcd_giveback_urb now gets executed in the hardirq > context, which causes problems for KCOV and KMSAN. > > One problem is that KCOV now is unable to collect coverage from > the USB code that gets executed from the dummy_hcd's timer callback, > as KCOV cannot collect coverage in the hardirq context. > > Another problem is that the dummy_hcd hrtimer might get triggered in the > middle of a softirq with KCOV remote coverage collection enabled, and tha= t > causes a WARNING in KCOV, as reported by syzbot. (I sent a separate patch > to shut down this WARNING, but that doesn't fix the other two issues.) > > Finally, KMSAN appears to ignore tracking memory copying operations > that happen in the hardirq context, which causes false positive > kernel-infoleaks, as reported by syzbot. > > Change the hrtimer in dummy_hcd to execute the callback in the softirq > context. > > Reported-by: syzbot+2388cdaeb6b10f0c13ac@syzkaller.appspotmail.com > Closes: https://syzkaller.appspot.com/bug?extid=3D2388cdaeb6b10f0c13ac > Reported-by: syzbot+17ca2339e34a1d863aad@syzkaller.appspotmail.com > Closes: https://syzkaller.appspot.com/bug?extid=3D17ca2339e34a1d863aad > Fixes: a7f3813e589f ("usb: gadget: dummy_hcd: Switch to hrtimer transfer = scheduler") > Cc: stable@vger.kernel.org > Signed-off-by: Andrey Konovalov Hi Greg, Could you pick up either this or Marcello's patch (https://lkml.org/lkml/2024/6/26/969)? In case they got lost. Thank you!