From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 E33A3175A8B; Sat, 18 Jul 2026 00:00:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784332815; cv=none; b=brdFbDPu6QMGx/i2/sdzrWumFxYQHqw0TB7cdeUKuIGhTvg1G4352Do5i3wsepg5m8eGkAjaUDJk6mTlVvZM03QAnJhqkiuaT4KgZLS4ufMRXAgzUB462t4xLfyHBEuIH0IZmzuMmgzf2EQzGqQbJQlOTbLgOvOaIVAANcelfxo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784332815; c=relaxed/simple; bh=S4MjSJH8kKZ5cbatkGmWZOhsb/FhATKRz9HOMUbArYU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=lsFFkxOahuO7/wsORbXhdXxeilpOF75joFbV7C3gr+l1TvmRSzlXvui2Tr4OnoqYjigEdiiQw7mXg+XWxfUR77zb2jcaLUO4EggdvPcsseXTM1vqEsWuvvR7ZU+7JnDmU+HXIxBLbxWFsc+jelYQGpm2tJZQ9OKWk+EtvJMTEIU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=CiHGZQni; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="CiHGZQni" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 117AD1F000E9; Sat, 18 Jul 2026 00:00:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784332813; bh=vx/1W3ASfCVSI1+TnaFoLicuyre8k2pmNf54ghLrbFg=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=CiHGZQnihy/9CHtgE2dzXcNtjhnY8ODCogd+7UndlAkGpnJ2bb1JAElCFAbo0FHMK 4VVFWkymezZgoYcdFBFTTJqFXRhPVI4b/M21qR6aAvCKVQsT0Gcav3gRLQtSPylB+j PMDwY2bEvzNmCcbdwL9aF7a8jVy/NNd9RbSNxVdFA5iY1Qy4+eOQ3GPvIaDl8yd6Ae x5GN3PygEIWU6v6lbSrCxbng3EbgUwISSxq+nbcrQ64K6RhGGJjDXpk+qWtIikFzCs 537GY8yikzEGB6YZlso3AWqySHeeVj1RsXrRZVBGv36KC3Bg8slcyRkovweMfunv48 Vr9cwPpywSmJA== From: SJ Park To: Hongfu Li Cc: SJ Park , akpm@linux-foundation.org, david@kernel.org, ljs@kernel.org, liam@infradead.org, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, shuah@kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, Hongfu Li Subject: Re: [PATCH] selftests/mm: Fix BUG_ON checking wrong variable in mremap_dontunmap Date: Fri, 17 Jul 2026 17:00:09 -0700 Message-ID: <20260718000010.85576-1-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260717070251.73212-1-hongfu.li@linux.dev> References: Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On Fri, 17 Jul 2026 15:02:51 +0800 Hongfu Li wrote: > From: Hongfu Li > > In mremap_dontunmap_partial_mapping_overwrite(), mremap() stores its > returned remapped address into remapped_mapping, while the BUG_ON > incorrectly checks dest_mapping instead. > > If mremap() fails, dest_mapping still holds a valid pointer obtained from > the prior mmap() call, making this BUG_ON never trigger at all. Correct > the check to validate the actual mremap() return value stored in > remapped_mapping. Nice catch. > > Signed-off-by: Hongfu Li Reviewed-by: SJ Park Thanks, SJ [...]