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 D753F26461E; Tue, 8 Apr 2025 12:37:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744115842; cv=none; b=iVuQinFEseFNHy+ubjGrB8oZ4N+Ucqe3XnTrwu27/w2i+cw2StBafGW5qyJTBAcw2P8lOlKoF8xSSespmsgLOA4OjB4zqCuauJ8IZ4rZ5Xyu/4cRusNkeDXgb8IVWJgW6IFO+jIAryPEc4xwKnZMywkh4EChJB6qSv4Uk/9bw38= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744115842; c=relaxed/simple; bh=jC5zqoAMwYlJiMnZCEW7JKFPNLdZtuzP0AzfhP8/Nw8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=sp5kgof100Tn9qFwpPwCcuKHa2F7cUqMkq9DoFUJ34ZWVRPaZsR8otbn6szo9QOCr5SpJy5CbEUtg6S5AWBsF4ZfFP2cuMS9OR5v/RN1rIrZSF0nXixtIdOPnLKjtwGj7SewZaWfh14XStAU+RIBxT1645D7jQ6neJman2zphjQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ZSE/o8Pw; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="ZSE/o8Pw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 68916C4CEE5; Tue, 8 Apr 2025 12:37:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1744115842; bh=jC5zqoAMwYlJiMnZCEW7JKFPNLdZtuzP0AzfhP8/Nw8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZSE/o8PwhgKzPqZHVjKlM20Kb84yNEu0AK6sATtriRcdXZJYJToacZrctSKElfMkA WOLb0mA5Zfs3aOrHu1ev3AZjsIyY0XvCRv6SbjV7iOzTvbnX62q7wwKw4iSKOlIWF2 9qO4U9z8TA88iesrho3MJ7UViPtbX3oXMckBqcJ4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Johannes Berg , Miri Korenblit , Sasha Levin Subject: [PATCH 6.1 126/204] wifi: iwlwifi: fw: allocate chained SG tables for dump Date: Tue, 8 Apr 2025 12:50:56 +0200 Message-ID: <20250408104824.004212044@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250408104820.266892317@linuxfoundation.org> References: <20250408104820.266892317@linuxfoundation.org> User-Agent: quilt/0.68 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 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johannes Berg [ Upstream commit 7774e3920029398ad49dc848b23840593f14d515 ] The firmware dumps can be pretty big, and since we use single pages for each SG table entry, even the table itself may end up being an order-5 allocation. Build chained tables so that we need not allocate a higher-order table here. This could be improved and cleaned up, e.g. by using the SG pool code or simply kvmalloc(), but all of that would require also updating the devcoredump first since that frees it all, so we need to be more careful. SG pool might also run against the CONFIG_ARCH_NO_SG_CHAIN limitation, which is irrelevant here. Also use _devcd_free_sgtable() for the error paths now, much simpler especially since it's in two places now. Signed-off-by: Johannes Berg Signed-off-by: Miri Korenblit Link: https://patch.msgid.link/20250209143303.697c7a465ac9.Iea982df46b5c075bfb77ade36f187d99a70c63db@changeid Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin --- drivers/net/wireless/intel/iwlwifi/fw/dbg.c | 86 ++++++++++++++------- 1 file changed, 58 insertions(+), 28 deletions(-) diff --git a/drivers/net/wireless/intel/iwlwifi/fw/dbg.c b/drivers/net/wireless/intel/iwlwifi/fw/dbg.c index 7fadaec777cea..4c5dbd8248e7b 100644 --- a/drivers/net/wireless/intel/iwlwifi/fw/dbg.c +++ b/drivers/net/wireless/intel/iwlwifi/fw/dbg.c @@ -559,41 +559,71 @@ static void iwl_dump_prph(struct iwl_fw_runtime *fwrt, } /* - * alloc_sgtable - allocates scallerlist table in the given size, - * fills it with pages and returns it + * alloc_sgtable - allocates (chained) scatterlist in the given size, + * fills it with pages and returns it * @size: the size (in bytes) of the table -*/ -static struct scatterlist *alloc_sgtable(int size) + */ +static struct scatterlist *alloc_sgtable(ssize_t size) { - int alloc_size, nents, i; - struct page *new_page; - struct scatterlist *iter; - struct scatterlist *table; + struct scatterlist *result = NULL, *prev; + int nents, i, n_prev; nents = DIV_ROUND_UP(size, PAGE_SIZE); - table = kcalloc(nents, sizeof(*table), GFP_KERNEL); - if (!table) - return NULL; - sg_init_table(table, nents); - iter = table; - for_each_sg(table, iter, sg_nents(table), i) { - new_page = alloc_page(GFP_KERNEL); - if (!new_page) { - /* release all previous allocated pages in the table */ - iter = table; - for_each_sg(table, iter, sg_nents(table), i) { - new_page = sg_page(iter); - if (new_page) - __free_page(new_page); - } - kfree(table); + +#define N_ENTRIES_PER_PAGE (PAGE_SIZE / sizeof(*result)) + /* + * We need an additional entry for table chaining, + * this ensures the loop can finish i.e. we can + * fit at least two entries per page (obviously, + * many more really fit.) + */ + BUILD_BUG_ON(N_ENTRIES_PER_PAGE < 2); + + while (nents > 0) { + struct scatterlist *new, *iter; + int n_fill, n_alloc; + + if (nents <= N_ENTRIES_PER_PAGE) { + /* last needed table */ + n_fill = nents; + n_alloc = nents; + nents = 0; + } else { + /* fill a page with entries */ + n_alloc = N_ENTRIES_PER_PAGE; + /* reserve one for chaining */ + n_fill = n_alloc - 1; + nents -= n_fill; + } + + new = kcalloc(n_alloc, sizeof(*new), GFP_KERNEL); + if (!new) { + if (result) + _devcd_free_sgtable(result); return NULL; } - alloc_size = min_t(int, size, PAGE_SIZE); - size -= PAGE_SIZE; - sg_set_page(iter, new_page, alloc_size, 0); + sg_init_table(new, n_alloc); + + if (!result) + result = new; + else + sg_chain(prev, n_prev, new); + prev = new; + n_prev = n_alloc; + + for_each_sg(new, iter, n_fill, i) { + struct page *new_page = alloc_page(GFP_KERNEL); + + if (!new_page) { + _devcd_free_sgtable(result); + return NULL; + } + + sg_set_page(iter, new_page, PAGE_SIZE, 0); + } } - return table; + + return result; } static void iwl_fw_get_prph_len(struct iwl_fw_runtime *fwrt, -- 2.39.5