From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C89B3C83F1C for ; Mon, 28 Aug 2023 10:51:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232153AbjH1Kul (ORCPT ); Mon, 28 Aug 2023 06:50:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35936 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232184AbjH1KuT (ORCPT ); Mon, 28 Aug 2023 06:50:19 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1DB1CCEB for ; Mon, 28 Aug 2023 03:49:54 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id EDEC063829 for ; Mon, 28 Aug 2023 10:49:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0DA03C433C7; Mon, 28 Aug 2023 10:49:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1693219793; bh=XpYSADRdeKs/1iC94s2y4DxGeJqUpSASB3VyUsl03iA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZunYLFUZNXIePcG30DjRwDOwxPJm8lRWKYgASHEQ0ECQNNIc43//R3GZ5o9eNJq9R pG6gWBny8gv+7hzbIJkTJKcWuOgZoQvbHOjUHK/CS6cbe2pb4UkWgRCaBask+AY9Mo Vm5drUdkcv60M1XwyCpgaTe2tcxVi4VBJFQcn4Kw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Dylan Jhong , Alexandre Ghiti , Christoph Hellwig , Palmer Dabbelt , Andrew Morton Subject: [PATCH 5.10 45/84] mm: add a call to flush_cache_vmap() in vmap_pfn() Date: Mon, 28 Aug 2023 12:14:02 +0200 Message-ID: <20230828101150.791841642@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230828101149.146126827@linuxfoundation.org> References: <20230828101149.146126827@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alexandre Ghiti commit a50420c79731fc5cf27ad43719c1091e842a2606 upstream. flush_cache_vmap() must be called after new vmalloc mappings are installed in the page table in order to allow architectures to make sure the new mapping is visible. It could lead to a panic since on some architectures (like powerpc), the page table walker could see the wrong pte value and trigger a spurious page fault that can not be resolved (see commit f1cb8f9beba8 ("powerpc/64s/radix: avoid ptesync after set_pte and ptep_set_access_flags")). But actually the patch is aiming at riscv: the riscv specification allows the caching of invalid entries in the TLB, and since we recently removed the vmalloc page fault handling, we now need to emit a tlb shootdown whenever a new vmalloc mapping is emitted (https://lore.kernel.org/linux-riscv/20230725132246.817726-1-alexghiti@rivosinc.com/). That's a temporary solution, there are ways to avoid that :) Link: https://lkml.kernel.org/r/20230809164633.1556126-1-alexghiti@rivosinc.com Fixes: 3e9a9e256b1e ("mm: add a vmap_pfn function") Reported-by: Dylan Jhong Closes: https://lore.kernel.org/linux-riscv/ZMytNY2J8iyjbPPy@atctrx.andestech.com/ Signed-off-by: Alexandre Ghiti Reviewed-by: Christoph Hellwig Reviewed-by: Palmer Dabbelt Acked-by: Palmer Dabbelt Reviewed-by: Dylan Jhong Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- mm/vmalloc.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -2453,6 +2453,10 @@ void *vmap_pfn(unsigned long *pfns, unsi free_vm_area(area); return NULL; } + + flush_cache_vmap((unsigned long)area->addr, + (unsigned long)area->addr + count * PAGE_SIZE); + return area->addr; } EXPORT_SYMBOL_GPL(vmap_pfn);