From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 4D1C11799F for ; Wed, 8 Oct 2025 04:25:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759897535; cv=none; b=m9gBztxCbulbTQ7Tf2bOgIerjDT69MTFhA0DDLn7PzTAy7u2d2lG0gpH0y6qqLInu0qiE3rdVuiANxLF6mdKjHMnNqdhJYoXiXiGg8jD7DByfqSIPFwLfTUC4ol7pFy+wMxkpDqCTtiCdI7CkmBktbRUI1FfaMo0F2GlQP4eYrU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759897535; c=relaxed/simple; bh=jKEXlct6Rf7OrDLOu0C95ftu6OrVnaetHPVagll4+7E=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Hvlnx/O7gZXZ7HPJk9obNcfZKoZHI4kP7feiHBzlOAWZREu5WPM0qYiC7Wlj87T2dwpmPngT0FZcDnY1EtAd0mmX3ts+rPw3QTLgDfaYcxnvyXJUORYo7pr/JVCYfgXpNyKcGfR7Rq7mAiivhXpxdUE4WLKE+SFW+I5zTxLa92A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C70E022EE; Tue, 7 Oct 2025 21:25:24 -0700 (PDT) Received: from [10.163.36.4] (unknown [10.163.36.4]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 595B63F738; Tue, 7 Oct 2025 21:25:31 -0700 (PDT) Message-ID: <4bf3894a-1825-447a-8efd-64ecc09e2dc6@arm.com> Date: Wed, 8 Oct 2025 09:55:28 +0530 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] drivers/sgi-gru: Use pxdp_get() for page table access To: linux-kernel@vger.kernel.org Cc: Dimitri Sivanich , Arnd Bergmann , Greg Kroah-Hartman References: <20251008042126.2408106-1-anshuman.khandual@arm.com> Content-Language: en-US From: Anshuman Khandual In-Reply-To: <20251008042126.2408106-1-anshuman.khandual@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 08/10/25 9:51 AM, Anshuman Khandual wrote: > Replace all READ_ONCE() with a standard page table accessors i.e pxdp_get() > that default into READ_ONCE() in cases where platforms do not override. > > Cc: Dimitri Sivanich > Cc: Arnd Bergmann > Cc: Greg Kroah-Hartman > Cc: linux-kernel@vger.kernel.org > Signed-off-by: Anshuman Khandual > --- > drivers/misc/sgi-gru/grufault.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/drivers/misc/sgi-gru/grufault.c b/drivers/misc/sgi-gru/grufault.c > index 3557d78ee47a..60e55facd8d7 100644 > --- a/drivers/misc/sgi-gru/grufault.c > +++ b/drivers/misc/sgi-gru/grufault.c > @@ -212,19 +212,19 @@ static int atomic_pte_lookup(struct vm_area_struct *vma, unsigned long vaddr, > pte_t pte; > > pgdp = pgd_offset(vma->vm_mm, vaddr); > - if (unlikely(pgd_none(*pgdp))) > + if (unlikely(pgd_none(pgdp_get(pgdp)))) > goto err; > > p4dp = p4d_offset(pgdp, vaddr); > - if (unlikely(p4d_none(*p4dp))) > + if (unlikely(p4d_none(p4dp_get(p4dp)))) > goto err; > > pudp = pud_offset(p4dp, vaddr); > - if (unlikely(pud_none(*pudp))) > + if (unlikely(pud_none(pudp_get(pudp)))) > goto err; > > pmdp = pmd_offset(pudp, vaddr); > - if (unlikely(pmd_none(*pmdp))) > + if (unlikely(pmd_none(pmdp_get(pmdp)))) > goto err; > #ifdef CONFIG_X86_64 > if (unlikely(pmd_leaf(*pmdp))) Please ignore this patch as it does not replace any READ_ONCE() based page table accesses in this file. My bad.