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 E18102C87B; Fri, 24 Nov 2023 18:56:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Otz+U6cs" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 194D4C433C8; Fri, 24 Nov 2023 18:56:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1700852180; bh=aPkL6j+4elro8eRCwexqZCpJ+bOhNiYA0oKiMkN2TBI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Otz+U6cslDFQ6PbwjRsZsdwUYrIkui16Db6dcB7rq5ZaLninYkq/1IBcNMBzIOdw9 uuJefvqFlBfLFhNWTfPKHUYMBfzSmjiIBLcB4lc8BKtAmRY/DJt7S2QjHnETrGhVst jSWt5R/meR0YzYGawm56r1U2RMfRIyYHd6nH/wuI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Claudio Imbrenda , Heiko Carstens , Vasily Gorbik Subject: [PATCH 6.1 252/372] s390/cmma: fix detection of DAT pages Date: Fri, 24 Nov 2023 17:50:39 +0000 Message-ID: <20231124172018.925475633@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231124172010.413667921@linuxfoundation.org> References: <20231124172010.413667921@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 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Heiko Carstens commit 44d93045247661acbd50b1629e62f415f2747577 upstream. If the cmma no-dat feature is available the kernel page tables are walked to identify and mark all pages which are used for address translation (all region, segment, and page tables). In a subsequent loop all other pages are marked as "no-dat" pages with the ESSA instruction. This information is visible to the hypervisor, so that the hypervisor can optimize purging of guest TLB entries. The initial loop however is incorrect: only the first three of the four pages which belong to segment and region tables will be marked as being used for DAT. The last page is incorrectly marked as no-dat. This can result in incorrect guest TLB flushes. Fix this by simply marking all four pages. Cc: Reviewed-by: Claudio Imbrenda Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik Signed-off-by: Greg Kroah-Hartman --- arch/s390/mm/page-states.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/arch/s390/mm/page-states.c +++ b/arch/s390/mm/page-states.c @@ -132,7 +132,7 @@ static void mark_kernel_pud(p4d_t *p4d, continue; if (!pud_folded(*pud)) { page = phys_to_page(pud_val(*pud)); - for (i = 0; i < 3; i++) + for (i = 0; i < 4; i++) set_bit(PG_arch_1, &page[i].flags); } mark_kernel_pmd(pud, addr, next); @@ -153,7 +153,7 @@ static void mark_kernel_p4d(pgd_t *pgd, continue; if (!p4d_folded(*p4d)) { page = phys_to_page(p4d_val(*p4d)); - for (i = 0; i < 3; i++) + for (i = 0; i < 4; i++) set_bit(PG_arch_1, &page[i].flags); } mark_kernel_pud(p4d, addr, next); @@ -182,7 +182,7 @@ static void mark_kernel_pgd(void) continue; if (!pgd_folded(*pgd)) { page = phys_to_page(pgd_val(*pgd)); - for (i = 0; i < 3; i++) + for (i = 0; i < 4; i++) set_bit(PG_arch_1, &page[i].flags); } mark_kernel_p4d(pgd, addr, next);