From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 62069C5DF81 for ; Wed, 19 Aug 2026 23:11:55 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 6B7F46B00BC; Wed, 19 Aug 2026 19:11:54 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 68FF36B00BD; Wed, 19 Aug 2026 19:11:54 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5A5796B00BE; Wed, 19 Aug 2026 19:11:54 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 3B0886B00BC for ; Wed, 19 Aug 2026 19:11:54 -0400 (EDT) Received: from smtpin27.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay02.hostedemail.com (Postfix) with ESMTP id AFE96120688 for ; Wed, 19 Aug 2026 23:11:53 +0000 (UTC) X-FDA: 85119568506.27.62CA39A Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf24.hostedemail.com (Postfix) with ESMTP id D6C4E180009 for ; Wed, 19 Aug 2026 23:11:51 +0000 (UTC) Authentication-Results: imf24.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b="UEo/GcvL"; spf=pass (imf24.hostedemail.com: domain of brauner@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=brauner@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1787181111; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=+eE/AORVX+nBzdLhuXTjCNB11etNcl4Di3dO/GDhzUg=; b=NHNshSsHybgGbFZA6YVnY6Qk0l8HD7HM4EntvYWi2LhK0p2xDewmrzdyLafgxishTKoH9/ CLglKX9Y2IWATFByklllLO8RLYnxXa/uRk0BjBD2TxztYyFETm4sfruO3i1mKotqE7HTU2 ebHmVyuAaaYvlvOTgwOSL+CD1A5bqAI= ARC-Authentication-Results: i=1; imf24.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b="UEo/GcvL"; spf=pass (imf24.hostedemail.com: domain of brauner@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=brauner@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1787181112; b=k2ILDI0ovFar0gleKSrR2UDpGKNlKznD/4L+/Hp6k3sGReVCbHZPgaJiZBonvndcbfSUZy Sj3RV8hWSNKOULqSkK8AaQYfEhg/QEaAj/Jl8nTrpgXk5gWUdidmGxSjF05JfkzKLGW3KN nZ71MSHSYTSmlXbLxtmtEUITysGS3xU= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 3CB9240BF4; Wed, 19 Aug 2026 23:11:51 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7BF091F00A3D; Wed, 19 Aug 2026 23:11:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1787181111; bh=+eE/AORVX+nBzdLhuXTjCNB11etNcl4Di3dO/GDhzUg=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=UEo/GcvLbLse8DiCCa3t7vPZHj60cEF3fZrSik9Od4RpIOFSFmMwo7fEUfZgZR7Pt udxRLnjSlYQv3oQqouyBpSyVJ6zf6n9Gy6bkUImPErHml4pJMDGP/IlljQbGMNFE04 A9TSHt3Ty9JknWI0dDqGELgO+d9HDU+otlMyoh1+dmSL4Jm4iKqraFCz3Frums7sDZ LJ/mF44Lqx0HvnRhIYyIVcXddqyH3nvErDW/W1fcMaloLXs84ii1v4U5HDOoHgdSz8 unuwJWVOrMcWushztXgAFusUL71pcM4wVr2qDXyb1WFG9jdw5B6V6rQhddIwtTMFNl rF5qLRVxZxzvQ== From: Christian Brauner Date: Thu, 20 Aug 2026 01:09:37 +0200 Subject: [PATCH v2 20/22] selftests/coredump: put a hole in the middle of a sparse mapping MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260820-work-coredump-sparse-v2-20-ba32dd718c51@kernel.org> References: <20260820-work-coredump-sparse-v2-0-ba32dd718c51@kernel.org> In-Reply-To: <20260820-work-coredump-sparse-v2-0-ba32dd718c51@kernel.org> To: linux-fsdevel@vger.kernel.org Cc: Jacob Lalonde , Josef Bacik , Jann Horn , Alexander Viro , Jan Kara , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Omar Sandoval , Jacob Lalonde , Shuah Khan , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, "Christian Brauner (Amutable)" X-Mailer: b4 0.17-dev-362b8 X-Developer-Signature: v=1; a=openpgp-sha256; l=1482; i=brauner@kernel.org; h=from:subject:message-id; bh=CDf2/UuMc2XBowFgVdwGiPjPw3vkqMeWbhqWHKnJoXk=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMWS1me9vF+H9di5sY8ORyo2Z2qz/hCYU/K/5+HdTcsiVe cuKvmaFdpSyMIhxMciKKbI4tJuEyy3nqdhslKkBM4eVCWQIAxenAEzkgz/DXznjj78+PZreIRbI +6nK0qx146GMc785hBbGqdUv+HuQOYnhv29pM/eVHcLM3xs938SYnmKtqXRtfqxaKHxaXU953YM 8LgA= X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: D6C4E180009 X-Stat-Signature: 5iykcz6grtkmd76ufjejzwk4ezifh1ur X-Rspam-User: X-HE-Tag: 1787181111-414515 X-HE-Meta: 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 nAN6aGgT PH8RYVhefH809plT9oOiKQy5ZyJqcwLFhvJgGYjzL7pypf/SEWSX3vlpT8CoKzxlosfkzBBFLDUTFKda0q35X7xbVKJuDu/cSWTb8yXjAUFPaN5LHYBSWV+2NuQAixC+Cteu/Wbvug01lFVTwvJ21lT31fO4K8/d3Chb8duaLiKHREMUeUGrSrBQYFa7n2qOKxDECjIjCqNz5VxLEG8wlWcaAy9VzXGOvWT3Q9JmqSjapI8imd75OwjBzeONHSDncJgZycyNRQkAyMxavoDX4VmmLJg== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: The crashing_child_sparse() helper touches the first page of the mapping. That forces everything behind it to be a trailing hole. This is easy to handle. Make the test more difficult meaningful by also touchin the last page. This causes the hole to sit between two populated pages. Signed-off-by: Christian Brauner (Amutable) --- tools/testing/selftests/coredump/coredump_test_helpers.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/coredump/coredump_test_helpers.c b/tools/testing/selftests/coredump/coredump_test_helpers.c index 45d76fa0f469..89f3954c5607 100644 --- a/tools/testing/selftests/coredump/coredump_test_helpers.c +++ b/tools/testing/selftests/coredump/coredump_test_helpers.c @@ -58,14 +58,16 @@ void crashing_child_sparse(size_t size) char *p; /* - * Touch the first page only. The whole mapping is dumped because - * it has been written to, but all of it save that one page is a - * hole. + * Touch the first and the last page. This will cause the whole mapping + * to be dumped because it has been written to. Everything between + * those two pages is a hole though. */ p = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE, -1, 0); - if (p != MAP_FAILED) + if (p != MAP_FAILED) { p[0] = 'x'; + p[size - 1] = 'x'; + } /* crash on purpose */ *(volatile int *)NULL = 0; -- 2.53.0