From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qt1-f169.google.com (mail-qt1-f169.google.com [209.85.160.169]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 510522594B3 for ; Thu, 12 Dec 2024 01:17:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.160.169 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733966245; cv=none; b=tu96lOwMPo4xYk9ykKwcg1cjvvCzdhSwvDEOBT17fIJSyei/2vOl4mNMP9sHWAKA0s6FT48YTwQULbfLgky4S1RIvvHfCrFbJK6AfAJuMGxwLUlhJSGL4WkC2E8wsSSNMqhAjCbukQyTj4hLOIknhXx4owdnQuWV6YiNHSR+tBc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733966245; c=relaxed/simple; bh=MvKagAzNUAOxChvHrOFpcJiYAyut8t9DL+GIvcj3XxM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=aNjNXdeR78/L4eMeBrgQbte6x78V0VfdmvMBS2uwS6Bu4C4GC4mg4GqFsDsrS+xWTE3SN3/ikuvjYt1hN3xMTZQ7+/s1maTSn1RJZQKjaI+YkdXQUYChds/ezzrx8DWw+5Z7mTlNhh5ruNVE3NsPIF2OGditJNUX1jw41xrzaEc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=cmpxchg.org; spf=pass smtp.mailfrom=cmpxchg.org; dkim=pass (2048-bit key) header.d=cmpxchg-org.20230601.gappssmtp.com header.i=@cmpxchg-org.20230601.gappssmtp.com header.b=zwmFQjWP; arc=none smtp.client-ip=209.85.160.169 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=cmpxchg.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=cmpxchg.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=cmpxchg-org.20230601.gappssmtp.com header.i=@cmpxchg-org.20230601.gappssmtp.com header.b="zwmFQjWP" Received: by mail-qt1-f169.google.com with SMTP id d75a77b69052e-46769b34cbfso1411551cf.0 for ; Wed, 11 Dec 2024 17:17:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cmpxchg-org.20230601.gappssmtp.com; s=20230601; t=1733966242; x=1734571042; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=djWQoJOklaLH0BLuJ8p0AL7/ItgSiiuZQ01XKXXCzcE=; b=zwmFQjWPIQ/ZCWJaEHQD4dRgzdgNdyqEGCh1OCIyQ2ss11AckZnocFl86q1PCVzNxw Yp1RLQq9u64Obw8q51az/txvhmQDPhvoJNpTjZXNaZ3sDJLJSekrE47INhnfW/BBXvvn Pub9wHh65Dn/LOuCUmUs8x1ttN2SAfU5uJd1xHtv75K6o2yMFMy+tCUfD4HKfT91Dfh7 oow30SqjMv2wkDd6zeaYZhKI7inFywq+cC0tKzxuIvl90k5I3S55nzUAOJIlwAnXOghY 9AtkTkWwgB2TEQt8oSwdpdRxr0kq3rsGkuPkN+JCBXGU+z2gpsYfNsRax4szJoZiMPP2 nfOg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1733966242; x=1734571042; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=djWQoJOklaLH0BLuJ8p0AL7/ItgSiiuZQ01XKXXCzcE=; b=Et7L+lD7ldBV4giMt7myIT45GzNQaruA+0eXBTrPrxTC7B5JmU5bbZlZxVjek6qx6U 9yaaVLn3PMKjBDv9J4xg70/doTCCAxDfyfQ92hpqXnbYhylHoTmhGiwUE+0qz3ZRv0qi P6xyaswG32toCzpBbxIjeIJ6PlkEfoHf/mIDil10MSt9ZWLGRjHpzo6xbLe0wzKvCX11 OQ+K2ryYhgqah0WzKgKjw6zCVoeJgptNiO+NxyPyurPYeE3dnywB+tnf0KoP2A3RbXXl 4+oOUj9+hGJlCdumys140/9WPL03p31x5SfeLW5Pi1zYEOeJ92qj00GXVy7hAkDYsA87 /MqA== X-Forwarded-Encrypted: i=1; AJvYcCVqFs4Y2O9Tj0OH9xNheDv+jNX0Q2nRc4ceNyIaw+s9Fxf5i4u6lWiwP3t6CpHNv/Y79Cwd7QDg@vger.kernel.org X-Gm-Message-State: AOJu0Yxf0vvRAIWLG3aV7XTMWyfvygp3U2uJ/G+Bf8RGK/tiVIoe1z0O d0f5y+iTfouMfIYI9sjrBf20zpqSijX0fnF/XGJxy88Fn7ewkNruUzdj1T4/e70= X-Gm-Gg: ASbGncvqIKaYjS9DB4HzynxCNNUID6HdXkLSMu6Xggne9IMvEvnyN/8Wo/qqWLEjHf4 onS7E7aE7oJWOm4HnuwG36EVIJizMugcBc0G9Pa3JVwKBexPE2u5DrhOR3HMzCzbCbK0EpK28Xs Ju5lW0q+P8C4uuFfxE5omGQBnKYFMfSBhw7qllmtv6L1IjLbKXWCMymcbTeOBFvUi8jemc4wO2w d1JKCV3KS1pFN4dgKsPOu/ruueEWH5RhMzE74RBYQ8KYcwcTlWlnzY= X-Google-Smtp-Source: AGHT+IEnJPekbYQNH9UrAAv3zHb1sBsf3vy+46DjthV6gdW4FwtIgcVe9aICG/pyjcXAlON52ZvNYQ== X-Received: by 2002:a05:622a:1243:b0:467:6226:bfc1 with SMTP id d75a77b69052e-467961afa32mr29536261cf.29.1733966242116; Wed, 11 Dec 2024 17:17:22 -0800 (PST) Received: from localhost ([2603:7000:c01:2716:da5e:d3ff:fee7:26e7]) by smtp.gmail.com with ESMTPSA id d75a77b69052e-46780a93029sm21262041cf.84.2024.12.11.17.17.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 11 Dec 2024 17:17:20 -0800 (PST) Date: Wed, 11 Dec 2024 20:17:19 -0500 From: Johannes Weiner To: "Matthew Wilcox (Oracle)" Cc: Andrew Morton , Christoph Hellwig , linux-mm@kvack.org, Michal Hocko , Roman Gushchin , Shakeel Butt , Muchun Song , cgroups@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH v3] vmalloc: Fix accounting with i915 Message-ID: <20241212011719.GA1026@cmpxchg.org> References: <20241211202538.168311-1-willy@infradead.org> Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241211202538.168311-1-willy@infradead.org> On Wed, Dec 11, 2024 at 08:25:37PM +0000, Matthew Wilcox (Oracle) wrote: > If the caller of vmap() specifies VM_MAP_PUT_PAGES (currently only the > i915 driver), we will decrement nr_vmalloc_pages and MEMCG_VMALLOC in > vfree(). These counters are incremented by vmalloc() but not by vmap() > so this will cause an underflow. Check the VM_MAP_PUT_PAGES flag before > decrementing either counter. > > Fixes: b944afc9d64d (mm: add a VM_MAP_PUT_PAGES flag for vmap) > Cc: stable@vger.kernel.org > Signed-off-by: Matthew Wilcox (Oracle) > Acked-by: Johannes Weiner Nice, thanks, looks good to me.