From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=95.215.58.29 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793804172; b=j8W+Nru6OxEFz1T33/25oaG70zWYCnOdy1SkTSXLlJov/FnX8KPeaDfPUWdeJ1q/c6Bb ViEhl8ndYzXh428AoQzbrhOc6l5PEMFDmsobGRr+CsOy5mgFwh5HXvwcxjW6g5Q4yuTzX MOiZlEIWI1/cy/0vgEhIAnZ0xlwAGKk08nCaD1vTTx2oZ1T/+dB3HjlrZX8jfDZEikVXo VMcoMXKGWuu+U2o+JvW7SUstukQr/DviPPJOP+Z9M802LBUVudjH60uKiyubsYbKTDJBk ERpnP6RAb3+mYIt84QUGZTPFK1y1AeX5y0PbxAm6q72vN3HaVYCd+sIjXsWfV2KwHjQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793804172; h=DMARC-Filter:X-Envelope-To:DKIM-Signature:X-Envelope-To:Received: X-Mizu-Trace-ID:X-Migadu-Flow:From:To:Cc:Subject:Date:Message-ID: X-Mailer:MIME-Version:Content-Transfer-Encoding; bh=rNNVTnTy0cTlwSmGHiRKlZ2iEy2+6bJGyVdMK3sWxNI=; b=0pZmlqHO8+rEP0SmUvKcJrB0RyFtrHwxD5FWvUVjtNKt2VSstpYtq/7WKj9WriQ0A90O W2VaQVYkBZzxygnAU3svFdp1UBKMt3yFe01fKSJhGchvSbJLrVnm8aUHKU5T2W2r0Ez/f KE3MTCc1PrKr3fJsgSob+47F4nuvLUuHGmTUObCu5bLyj8atc4KK2i/W0zYN+RqEfzIyq TvGkO2F5NDwkbHLTN/sc71fzAY/Ja4004+VWrTdCMCrORVBf/1ztShqvLsaCmAzS4k4jG HYX62T0qNcsjtspVdlZcKsAfq7W9YTS7ueo9Xn1U+6wAb4TIvdCknqN9viUuRpJEU9g== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=luMnxL52; arc=none smtp.remote-ip=95.215.58.29 Received: from mta1.migadu.com (out-29.mta1.migadu.com [95.215.58.29]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0C068606A31B for ; Wed, 4 Nov 2026 14:56:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 0C068606A31B Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=luMnxL52 X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=WiQsxdd6QhzAPp2ldpcECaeiN+cck/9lOboIQqVqld8=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1793804168; v=1; x=1794408968; b=luMnxL5285DUzIM2AnuE7vWel01YwA/GscQp5xVB+8cHNDMDiOZSJ1K2BKeLcoMm3HYtfixX PC2yI/o6bOXb/2ZmmM/rU7qTaqvh6WDG6BELEtTyoO1wlDlh+yhQfa0VhyGoHUarl54v1XDvkGY 4P/osjJMqUFZVmeWRk762eWU= X-Envelope-To: linux-kernel@vger.kernel.org Received: by mta12.migadu.com with ESMTPS id f8a97d86c29cc177; Wed, 04 Nov 2026 14:56:07 +0000 X-Mizu-Trace-ID: f8a97d86c29cc177 X-Migadu-Flow: FLOW_OUT From: Usama Arif To: Andrew Morton , baoquan.he@linux.dev, rppt@kernel.org, pasha.tatashin@soleen.com, pratyush@kernel.org, ruirui.yang@linux.dev, jbohac@suse.cz, david@kernel.org, hbathini@linux.ibm.com, leitao@debian.org, kexec@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, kas@kernel.org, hannes@cmpxchg.org, riel@surriel.com, shakeel.butt@linux.dev, kernel-team@meta.com Cc: Usama Arif Subject: [PATCH] crash: keep crashkernel CMA pages reserved if activation fails Date: Wed, 4 Nov 2026 06:56:00 -0800 Message-ID: <20261104145600.3708886-1-usama.arif@linux.dev> X-Mailer: git-send-email 2.53.0 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit reserve_crashkernel_cma() adds each crashkernel CMA area to crashk_cma_ranges[] as soon as it is declared. If the area later fails activation, e.g. because movablecore= put the ZONE_MOVABLE boundary inside it, cma_activate_area() releases the pages to the buddy allocator as ordinary memory. The range is still handed to the crash kernel and excluded from the vmcore, so kernel data that lands there is overwritten by the crash kernel and missing from the dump. Mark the areas with cma_reserve_pages_on_error(), so that a failed activation leaves the pages reserved: lost to the first kernel, but safe for the crash kernel to use. Fixes: ab475510e042 ("kdump: implement reserve_crashkernel_cma") Signed-off-by: Usama Arif --- kernel/crash_reserve.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/crash_reserve.c b/kernel/crash_reserve.c index a03f0a4305a4e..a4b616ed49482 100644 --- a/kernel/crash_reserve.c +++ b/kernel/crash_reserve.c @@ -498,6 +498,7 @@ void __init reserve_crashkernel_cma(unsigned long long cma_size) continue; } + cma_reserve_pages_on_error(res); crashk_cma_ranges[crashk_cma_cnt].start = cma_get_base(res); crashk_cma_ranges[crashk_cma_cnt].end = crashk_cma_ranges[crashk_cma_cnt].start + -- 2.53.0-Meta