From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 203B86FB1; Tue, 5 Dec 2023 03:23:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="eoxnv5pM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id ADF92C433C8; Tue, 5 Dec 2023 03:23:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1701746639; bh=pkIddOl87x5w9buGM5J0axfucoL7rjEWa2PMtbleIK8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eoxnv5pMd80oKSWPY/zxqIsp/HZh/xXYItni+hYWlMKSwhxyZphGByQjkxirxv5wB S3NhdABn1kBPb7u6XOAATmeCIHqRI3wVAwjOF/59Y48usEeX/nSMFMu2WVzN6Con4F /q8C7584gFTbU6JfWPpWn27oEFxWbr5Q9qGGoUKg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Kirill A. Shutemov" , Michael Roth , Vlastimil Babka , Ard Biesheuvel , Sasha Levin Subject: [PATCH 6.6 100/134] efi/unaccepted: Fix off-by-one when checking for overlapping ranges Date: Tue, 5 Dec 2023 12:16:12 +0900 Message-ID: <20231205031541.774578565@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231205031535.163661217@linuxfoundation.org> References: <20231205031535.163661217@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Michael Roth [ Upstream commit 01b1e3ca0e5ce47bbae8217d47376ad01b331b07 ] When a task needs to accept memory it will scan the accepting_list to see if any ranges already being processed by other tasks overlap with its range. Due to an off-by-one in the range comparisons, a task might falsely determine that an overlapping range is being accepted, leading to an unnecessary delay before it begins processing the range. Fix the off-by-one in the range comparison to prevent this and slightly improve performance. Fixes: 50e782a86c98 ("efi/unaccepted: Fix soft lockups caused by parallel memory acceptance") Link: https://lore.kernel.org/linux-mm/20231101004523.vseyi5bezgfaht5i@amd.com/T/#me2eceb9906fcae5fe958b3fe88e41f920f8335b6 Reviewed-by: Kirill A. Shutemov Signed-off-by: Michael Roth Acked-by: Vlastimil Babka Signed-off-by: Ard Biesheuvel Signed-off-by: Sasha Levin --- drivers/firmware/efi/unaccepted_memory.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/firmware/efi/unaccepted_memory.c b/drivers/firmware/efi/unaccepted_memory.c index 135278ddaf627..79fb687bb90f9 100644 --- a/drivers/firmware/efi/unaccepted_memory.c +++ b/drivers/firmware/efi/unaccepted_memory.c @@ -100,7 +100,7 @@ void accept_memory(phys_addr_t start, phys_addr_t end) * overlap on physical address level. */ list_for_each_entry(entry, &accepting_list, list) { - if (entry->end < range.start) + if (entry->end <= range.start) continue; if (entry->start >= range.end) continue; -- 2.42.0