From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from cloud.peff.net (cloud.peff.net [217.216.95.84]) (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 127DF38D3F7 for ; Tue, 29 Sep 2026 20:41:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.216.95.84 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790714520; cv=none; b=SMybSGQaTaK8aSI+5MVRCf7H0BTnxX2yjXr3vvduOPrPAO86ebkBLBZ2qUCKBnkS/NwMVONBeQPrH7yoooJ+43G3CKeqRvkCTYIjYpoIezw5ioQQoC7N0Z/Da905mzfG2cyo/xfu+2FPs5r6NVi7Hn07sT/yPggdK6w/wkffJmc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790714520; c=relaxed/simple; bh=bMYwlIbYrdqGGhFTTckiSXR78WcT3d7rC8KRBe2s1b4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=JX6p0WTXvtoQ9LC7ElyB+sltPiJKQbHCjArKj2+rVfimdPoG3Go37ZEIHZJ66YcKCK4ewxb+XbJaMxf47BGtWxbDQJUJm3kpag4GgFiynBkF5f7u78xmV36TEwnCqQptK3zxhHKe9e9k6pDk3i3Aw0vmtUTCh4ZZSVK9lrF5uSk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=peff.net; spf=pass smtp.mailfrom=peff.net; dkim=pass (2048-bit key) header.d=peff.net header.i=@peff.net header.b=EmcrtYXu; arc=none smtp.client-ip=217.216.95.84 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=peff.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=peff.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=peff.net header.i=@peff.net header.b="EmcrtYXu" Received: (qmail 1399 invoked by uid 106); 29 Sep 2026 20:41:57 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed; d=peff.net; h=date:from:to:cc:subject:message-id:references:mime-version:content-type:in-reply-to; s=20240930; bh=bMYwlIbYrdqGGhFTTckiSXR78WcT3d7rC8KRBe2s1b4=; b=EmcrtYXuhkbYkzb+SqXRO2Czuehb+ORMWXbOdEUdDt5AEgF+E2QbevPEaqAXAJujVL1zzeE9u01QEU1rDZjMOLVQ2Brb8dLCaJ+Ykvv0RWrl2epixEPKtCZnsTv/Bjm3n1kpnxzSe+t7rNRKvnKgwHjE/nfEn0iwIL1Xi0jGtaJR4a9HVd3Qbxd9QXU5fZ6RQQOXGzPMqUeB4Ua9v2S3Iw/Y+Mz4BGvGXjO4ibjQrRg+LIEqOop6b5EMfdVtmpmhOXwlsp6aTGq7EKabR8j2CzIrD2dEM8tskH+0gJ8mWBV+0XczBQMwCvNlF62A6r/w1L346e9CJtUhxL89pI8YmA== Received: from Unknown (HELO peff.net) (10.0.1.2) by cloud.peff.net (qpsmtpd/0.94) with ESMTP; Tue, 29 Sep 2026 20:41:57 +0000 Authentication-Results: cloud.peff.net; auth=none Received: (qmail 3659 invoked by uid 111); 29 Sep 2026 20:41:57 -0000 Received: from coredump.intra.peff.net (HELO coredump.intra.peff.net) (10.0.0.2) by peff.net (qpsmtpd/0.94) with (TLS_AES_256_GCM_SHA384 encrypted) ESMTPS; Tue, 29 Sep 2026 16:41:57 -0400 Authentication-Results: peff.net; auth=none Date: Tue, 29 Sep 2026 16:41:57 -0400 From: Jeff King To: Junio C Hamano Cc: git@vger.kernel.org, Elijah Newren Subject: Re: [PATCH 4/5] merge-ll: use read_mmfile() to read external merge results Message-ID: <20260929204157.GA1733321@coredump.intra.peff.net> References: <20260929064935.GA1276867@coredump.intra.peff.net> <20260929065442.GD1697497@coredump.intra.peff.net> <20260929201134.GA1713437@coredump.intra.peff.net> Precedence: bulk X-Mailing-List: git@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20260929201134.GA1713437@coredump.intra.peff.net> On Tue, Sep 29, 2026 at 04:11:34PM -0400, Jeff King wrote: > I had imagined just fixing this in ll_ext_merge(), like: > [...] > which reduces the weirdness coming out of that function. But it wouldn't > help with other drivers (which may or may not have similar problems? I'd > guess not, since they are all operating internally). So here are patches to do that, including a cleaned-up version of the reproduction I posted. I think ll_ext_merge() is the only driver that has this weird error case, so it should be sufficient. Your patch would protect a potential future driver, but I'd be surprised if we had one that introduced the same NULL-but-not-an-error behavior. [6/5]: merge-ll: handle external driver status before reading result [7/5]: merge-ll: report an error when reading external merge results fails merge-ll.c | 14 ++++++------- t/t4200-rerere.sh | 51 +++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 58 insertions(+), 7 deletions(-) -Peff