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 D771B34CC3 for ; Wed, 7 Jun 2023 21:02:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5AF24C433EF; Wed, 7 Jun 2023 21:02:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1686171725; bh=7L8cY1/FfTpIww6poA0DK9pAvBkFIbJCwCOQD29Wgns=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vNVIBCSHsXHbD/VNB5BBaU22b+maLiCivJ5zregDDNslWXBPTaFNotWW1+B067vdu WSYvTQIK397PknK0sgzy4O8zWNs5U7OYqj9w7kxjm8COfMZCFe8MdZZ+iOWGNazDtJ mvBQdN+zj52f+COE/BTUPF+E5rIZ7NhdfIeh1RhA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Gaurav Batra , Brian King , Michael Ellerman Subject: [PATCH 5.15 126/159] powerpc/iommu: Limit number of TCEs to 512 for H_STUFF_TCE hcall Date: Wed, 7 Jun 2023 22:17:09 +0200 Message-ID: <20230607200907.802502332@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230607200903.652580797@linuxfoundation.org> References: <20230607200903.652580797@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Gaurav Batra commit 9d2ccf00bddc268045e3d65a8108d61ada0e4b4e upstream. Currently in tce_freemulti_pSeriesLP() there is no limit on how many TCEs are passed to the H_STUFF_TCE hcall. This has not caused an issue until now, but newer firmware releases have started enforcing a limit of 512 TCEs per call. The limit is correct per the specification (PAPR v2.12 ยง 14.5.4.2.3). The code has been in it's current form since it was initially merged. Cc: stable@vger.kernel.org Signed-off-by: Gaurav Batra Reviewed-by: Brian King [mpe: Tweak change log wording & add PAPR reference] Signed-off-by: Michael Ellerman Link: https://msgid.link/20230525143454.56878-1-gbatra@linux.vnet.ibm.com Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/platforms/pseries/iommu.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) --- a/arch/powerpc/platforms/pseries/iommu.c +++ b/arch/powerpc/platforms/pseries/iommu.c @@ -311,13 +311,22 @@ static void tce_free_pSeriesLP(unsigned static void tce_freemulti_pSeriesLP(struct iommu_table *tbl, long tcenum, long npages) { u64 rc; + long rpages = npages; + unsigned long limit; if (!firmware_has_feature(FW_FEATURE_STUFF_TCE)) return tce_free_pSeriesLP(tbl->it_index, tcenum, tbl->it_page_shift, npages); - rc = plpar_tce_stuff((u64)tbl->it_index, - (u64)tcenum << tbl->it_page_shift, 0, npages); + do { + limit = min_t(unsigned long, rpages, 512); + + rc = plpar_tce_stuff((u64)tbl->it_index, + (u64)tcenum << tbl->it_page_shift, 0, limit); + + rpages -= limit; + tcenum += limit; + } while (rpages > 0 && !rc); if (rc && printk_ratelimit()) { printk("tce_freemulti_pSeriesLP: plpar_tce_stuff failed\n");