From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-lf1-f48.google.com (mail-lf1-f48.google.com [209.85.167.48]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3E2F78C16 for ; Fri, 19 May 2023 12:09:40 +0000 (UTC) Received: by mail-lf1-f48.google.com with SMTP id 2adb3069b0e04-4f3af4295ddso607934e87.2 for ; Fri, 19 May 2023 05:09:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1684498178; x=1687090178; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:date:from:from:to:cc:subject:date:message-id:reply-to; bh=b7UdFp5GhAiSV0XORaYQNKiXNz/+Czt3HESIc1RiAg8=; b=SsTsyfOr21l+ewnUtIgEk7T27S/itlGotkVd0LvcJPueUZVCtnepavisOdEOzdjeXz hAg9fj7Vh0xUzAHeuuCRN8Lx1r0Fx6o1RbCZx5xblVRJTRMx4/zR2EJjUbOB+PRSXnXt uJLJssYxU3MxSSj+NjzRyk9tK3qomv+1GH45+LpYOImEIlmMcvL/RT0PJSzK3LQCvsY9 iS3oXXMFXZCpVEZjpWnqy4zoJZzx1DR2qK3cr0gNTjN/qfD1XF2NpZ3OHiK0EWfarwcu wZNS0OXn0qAW8bafFMKhre7LZQxW92UIBUubNy7MRrDHP7CDhS+pgLthZ2w6ZCKVwmh5 LCjg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684498178; x=1687090178; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:date:from:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=b7UdFp5GhAiSV0XORaYQNKiXNz/+Czt3HESIc1RiAg8=; b=dIDURb9trrI6cG56uJ69+CxEWxcY1xB5GvkTp/pKQckF0CIfpugXQeYAIP9SKUz6Df N6X+vve0idkFNe+QVAD/558muAJeIexb6cWj45wIuQK/dd5I7onxThmL3XNQp94OzemC nnd6rfqCSH1oNXST+vllfj35du6kjzeSjNipi3qkO6YFoL7HypneOGjXQK+3jgboLVo8 2qRdcO4KzLrBTxtYARtbO0hATkH8KF/C9wyix+VxZx8qwSU++HsXDxoJdSQuMZFo7dnm oC3X4bu92zulS6cAcwu1iIMsEQYpCZLj/38sax5gysGBG0LSs1AYedH8lZpmnlWI5nlP 83bA== X-Gm-Message-State: AC+VfDwQVB5lKIfRtY1xeh3/PP1AT8lTGjYiC5LbS1HYa5FvyPUw+1V7 R9MtFC0IhRVjMSyY9cPfohs= X-Google-Smtp-Source: ACHHUZ6chS+j6ik3EDwUZbqAeKYmkhlSk/4VlNyw4JPRLbolGOF1i2zWinXwEYOmyW0qHqk9zFDXSA== X-Received: by 2002:ac2:5fe6:0:b0:4ed:c639:54cd with SMTP id s6-20020ac25fe6000000b004edc63954cdmr633908lfg.35.1684498177856; Fri, 19 May 2023 05:09:37 -0700 (PDT) Received: from pc636 (host-90-235-19-70.mobileonline.telia.com. [90.235.19.70]) by smtp.gmail.com with ESMTPSA id n7-20020ac242c7000000b004f24cb9ef14sm582963lfl.47.2023.05.19.05.09.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 19 May 2023 05:09:37 -0700 (PDT) From: Uladzislau Rezki X-Google-Original-From: Uladzislau Rezki Date: Fri, 19 May 2023 14:09:34 +0200 To: Ryan Roberts Cc: Andrew Morton , SeongJae Park , Christoph Hellwig , "Matthew Wilcox (Oracle)" , "Kirill A. Shutemov" , Lorenzo Stoakes , Uladzislau Rezki , Zi Yan , linux-kernel@vger.kernel.org, linux-mm@kvack.org, damon@lists.linux.dev, Christoph Hellwig Subject: Re: [PATCH v2 1/5] mm: vmalloc must set pte via arch code Message-ID: References: <20230518110727.2106156-1-ryan.roberts@arm.com> <20230518110727.2106156-2-ryan.roberts@arm.com> Precedence: bulk X-Mailing-List: damon@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230518110727.2106156-2-ryan.roberts@arm.com> On Thu, May 18, 2023 at 12:07:23PM +0100, Ryan Roberts wrote: > It is bad practice to directly set pte entries within a pte table. > Instead all modifications must go through arch-provided helpers such as > set_pte_at() to give the arch code visibility and allow it to check > (and potentially modify) the operation. > > Fixes: 3e9a9e256b1e ("mm: add a vmap_pfn function") > Signed-off-by: Ryan Roberts > Reviewed-by: Zi Yan > Acked-by: Lorenzo Stoakes > Reviewed-by: Christoph Hellwig > --- > mm/vmalloc.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/mm/vmalloc.c b/mm/vmalloc.c > index 9683573f1225..48202ec5f79a 100644 > --- a/mm/vmalloc.c > +++ b/mm/vmalloc.c > @@ -2899,10 +2899,16 @@ struct vmap_pfn_data { > static int vmap_pfn_apply(pte_t *pte, unsigned long addr, void *private) > { > struct vmap_pfn_data *data = private; > + unsigned long pfn = data->pfns[data->idx]; > + pte_t ptent; > > - if (WARN_ON_ONCE(pfn_valid(data->pfns[data->idx]))) > + if (WARN_ON_ONCE(pfn_valid(pfn))) > return -EINVAL; > - *pte = pte_mkspecial(pfn_pte(data->pfns[data->idx++], data->prot)); > + > + ptent = pte_mkspecial(pfn_pte(pfn, data->prot)); > + set_pte_at(&init_mm, addr, pte, ptent); > + > + data->idx++; > return 0; > } > > -- > 2.25.1 > Reviewed-by: Uladzislau Rezki (Sony) -- Uladzislau Rezki