From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (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 81BDD47DD48 for ; Mon, 2 Mar 2026 19:44:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.50.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772480647; cv=none; b=mhLEe4TiP+ILE/mosDxBpq9Q9vV5D6g5MJMyTqrczEoUY2+qFyl9FKM4qJkZ6kJpoyr1sP71bkPHPWU32HZzvVvulCMVJJ2IcTCYzSjwuITkIWqpII0tpig32ojBZ+eVch73JuK5R54UKV6KKvXbi9xkSYcXWqP5V00K3Xm/aAg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772480647; c=relaxed/simple; bh=dFDf2OxM/13S7w8SgnnjRgSWYXGvvN+I2gQBaiqBQNI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=q1CBN1SLfUYZWrfcK+RXrSILdtLTlm6t4ulkBGUlr9Nf+v4KjCSzabiXBV00BJUdRbOgw/TSnb1InbGtSsO7zWV0zS1KMUBcxOPj8A64/zJfCFec/QvGcDCE7UcYKa0l9g60JDX4uEziOosRarj5ayjgd2kGYB3ED2i7GT0OYXo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=OV2ah41e; arc=none smtp.client-ip=90.155.50.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="OV2ah41e" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Transfer-Encoding: Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Sender:Reply-To:Content-ID:Content-Description; bh=6vt15uZt8IrKH04Okb5T1ldonx1OgDF1nKmGa7hSBso=; b=OV2ah41eLKpoVUjaguiN0ARl4w Nt1gPxhGSSabVVusnrKSgzX5c30fU6VbTpLStrdYa/mZmmwRWIt/68FQ32IKwhObM+00XmK8/kwb+ VPRw8kPmP9MhXIUDpuPC3tINAHSlY0+eBNp2QPiwbj+4n2CHzUZSztDGlue3Wx2aRlDp1d7TO80qT Z1KpIJO+NqgYcDzn1jD6R8KGZMKkH14yADaY5ITboMdi10IqFoq8nRpp56OEMG+OZPaLZ933VcqvR UWn/ScG9EU81bQ5stJMp2BMiYqsXKhpECU0EBBvSqd9RNCVZSiiKFqCTOzFsKVIwx4sLZLZSEtKr9 bPCYEMbQ==; Received: from willy by casper.infradead.org with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1vx9BT-00000009zSS-23Xc; Mon, 02 Mar 2026 19:44:03 +0000 Date: Mon, 2 Mar 2026 19:44:03 +0000 From: Matthew Wilcox To: Alexey Suchkov Cc: akpm@linux-foundation.org, dywoq.contact@gmail.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH] [PATCH v2] mm: initialize 'seq' in gup_fast to remove -Wmaybe-uninitialized warning Message-ID: References: <20260302191237.34375-1-dywoq.contact@gmail.com> <20260302193405.37961-1-dywoq.contact@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260302193405.37961-1-dywoq.contact@gmail.com> On Mon, Mar 02, 2026 at 10:34:05PM +0300, Alexey Suchkov wrote: > The local variable 'seq' in gup_fast (mm/gup.c) was declared > without initialization, which can trigger: > > mm/gup.c:3165:20: warning: ‘seq’ may be used uninitialized [-Wmaybe-uninitialized] > > Initialize 'seq' to 0. This does not change behavior, since > read_seqcount_retry() always writes to it before use. What compiler?