From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f73.google.com (mail-wm1-f73.google.com [209.85.128.73]) (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 B79581A0BD0 for ; Fri, 27 Mar 2026 09:31:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774603890; cv=none; b=V5BDrm5y2hRnuLduslu5qqLaGXbKMQC+pEvSEeJHjOpSM84f3yCI/0xCRtwCndqabInJ5ASbLQEwtB7EsnpYbEj0nV35WCa5jVm4z1WQgkXKpF3Pu3hoC0BEHMakUuesU/1g8MS/Q4Sjq3TAPkQDo5+bFGXl5AT730YKLLxhyyc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774603890; c=relaxed/simple; bh=aeLnTNdDTx+gmQNpElCgyL2BoFqNDRXhA3Sdxyz5kt0=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=iRnL8padBL1ge8QTu8BXKCqQYSl6mE9NpNw10axx97Z9PfALjlPcVj/LL3tpAWkDDsLkHwmIPiqBeCd/x3UUJVWynsdxrVsj9US8KjGoNuP6oReyUZHWPBAz6uODlbXqozecNfhyTSIEae2kzq4q9m76wUq98T1V3mwibjgOruo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--aliceryhl.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=BV7qu/2Q; arc=none smtp.client-ip=209.85.128.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--aliceryhl.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="BV7qu/2Q" Received: by mail-wm1-f73.google.com with SMTP id 5b1f17b1804b1-4853b5b0fafso27788885e9.3 for ; Fri, 27 Mar 2026 02:31:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1774603887; x=1775208687; darn=vger.kernel.org; h=content-transfer-encoding:cc:to:from:subject:message-id:references :mime-version:in-reply-to:date:from:to:cc:subject:date:message-id :reply-to; bh=V1OwEf8imgEcaY7dllHNGM8XinZT2Wtp74qO0bSsJFE=; b=BV7qu/2QKBwK41wfQwa7OO5+kEuSNzhGpyhAVcY9UyQIYIRhXsiLWWHW8N6o9AdffS qXsFVYui+03qjEm51Ks7fWUPAwpTKIaDvSJy5PnMUhwaLZusQbOsj2W5nPS023N483B/ dBE4cHQ/40G/hEy3CME8CpGQLPo5mRKn3mzvh3c28wKeQRq1fAxzN7TUo+rOEjtYhpIT qPl9Qzxsvky65eDA3mTGHvBnctukzZIQ2iF4z2+d4OWT26OPm3Zs4+aprExpfx8OUHie aPaxNGpmqIL6T/WQIXkTbbkgWTJDNE5cwuUab0MC9+5i/7G29IO6svbo5VIXeEQ6Fqgv lq7A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1774603887; x=1775208687; h=content-transfer-encoding:cc:to:from:subject:message-id:references :mime-version:in-reply-to:date:x-gm-message-state:from:to:cc:subject :date:message-id:reply-to; bh=V1OwEf8imgEcaY7dllHNGM8XinZT2Wtp74qO0bSsJFE=; b=UHbuFzKf8t5z2gqkpSQoe5XptT8Ct9oatKZrL0Hldmw+zOapHKYHi4xWCX6iMXwyyB S/FutC+h51P4QO0rjaKLPG5tF2FkeLNMt9fufkThSLB6NGZnae0IYvKOGRV6cxbijQc1 nfBhmqH7zmA207gtHbGTYADd8CZS64ugzs7l9y6/2Jhu40yIF+3Srs9ejRlt/xhzalQY pHSCOePmPbh6eboyE5binnZQf0bwpV2hgD+K2bcwz47hm84/3p8ul+iuGEQ/awi50rAp aDVXlDbpGNOyhO7xocSW+Jo0qWlcgPk53ScO1NpS62RiLsWvwupPJsC19ieQoTAkiQmF TYGg== X-Gm-Message-State: AOJu0YwYqOmbx/fQkidrx5jeVb3Ifceo86MRN59Rp0irc2eHTvttAjB7 AiZ3Ug579WBfu110sB2O8SNc9tamulhxw4V6pxkN6wDogvbYmQdCFX6vKGFOGq0cAHsUIY5X+1J 4xIazKQ0aL8REj1cW7Q== X-Received: from wmog15.prod.google.com ([2002:a05:600c:310f:b0:47f:941a:613d]) (user=aliceryhl job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:35c4:b0:485:353f:c651 with SMTP id 5b1f17b1804b1-48727eb7fcdmr29769655e9.22.1774603886661; Fri, 27 Mar 2026 02:31:26 -0700 (PDT) Date: Fri, 27 Mar 2026 09:31:25 +0000 In-Reply-To: <20260313150956.1618635-5-adrian.larumbe@collabora.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260313150956.1618635-1-adrian.larumbe@collabora.com> <20260313150956.1618635-5-adrian.larumbe@collabora.com> Message-ID: Subject: Re: [PATCH v5 04/11] drm/gpuvm: Add a helper to check if two VA can be merged From: Alice Ryhl To: "=?utf-8?Q?Adri=C3=A1n?= Larumbe" Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Steven Price , Boris Brezillon , Janne Grunau , kernel@collabora.com, Caterina Shablia , Danilo Krummrich , Matthew Brost , "Thomas =?utf-8?Q?Hellstr=C3=B6m?=" , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable On Fri, Mar 13, 2026 at 03:09:41PM +0000, Adri=C3=A1n Larumbe wrote: > From: Boris Brezillon >=20 > We are going to add flags/properties that will impact the VA merging > ability. Instead of sprinkling tests all over the place in > __drm_gpuvm_sm_map(), let's add a helper aggregating all these checks > can call it for every existing VA we walk through in the > __drm_gpuvm_sm_map() loop. >=20 > Signed-off-by: Boris Brezillon > Signed-off-by: Caterina Shablia > + /* We intentionally ignore u64 underflows because all we care about > + * here is whether the VA diff matches the GEM offset diff. > + */ > + return b->va.addr - a->va.addr =3D=3D b->gem.offset - a->gem.offset; Please use wrapping_sub() to make it clear to sanitizers etc that underflow is intentional in this case. Alice