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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D71D9C3DA7F for ; Wed, 7 Aug 2024 22:23:28 +0000 (UTC) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; secure) header.d=linutronix.de header.i=@linutronix.de header.a=rsa-sha256 header.s=2020 header.b=MjVStxYX; dkim=fail reason="signature verification failed" header.d=linutronix.de header.i=@linutronix.de header.a=ed25519-sha256 header.s=2020e header.b=s6thDodU; dkim-atps=neutral Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4WfPp73Ts0z3dRD for ; Thu, 8 Aug 2024 08:23:27 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; secure) header.d=linutronix.de header.i=@linutronix.de header.a=rsa-sha256 header.s=2020 header.b=MjVStxYX; dkim=pass header.d=linutronix.de header.i=@linutronix.de header.a=ed25519-sha256 header.s=2020e header.b=s6thDodU; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linutronix.de (client-ip=2a0a:51c0:0:12e:550::1; helo=galois.linutronix.de; envelope-from=tglx@linutronix.de; receiver=lists.ozlabs.org) Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4WfPnM4bpgz3cLj for ; Thu, 8 Aug 2024 08:22:47 +1000 (AEST) From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1723069359; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=D3f6AgGXBWn26USlUGHHAP7bmp83AGplRMWVB7u+gXs=; b=MjVStxYXCwpkumLfhgR5p8beZFpGH2nkbtVVALx+fFHnNmmYvlk9jeWFb2Q/rJYIvBu7Yf QmqhkyySGxyYRAosoZO89bM199kAIarC+9Nc93FIuUE3eN99+Tkwo61xTamSAX8SS3iNBN iIOfqCr4ykriRm5TOq0tu9JB41vbrUgGFzwYj/6wQo82k+sDITDg/nr4x7+tjiZXPLl4U6 ByrZvF9YgWAzEcjJn/hOUGeXT/RLW3uVgLtH+5n/Deqdx1JJpBwf45ixi5O+pKIQUNqlPh +oebXHH82ss0ROpqZQ7F6Euf9mWjW9YkHsMH+f61njOBq13jB7EdVgFLXZjNGA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1723069359; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=D3f6AgGXBWn26USlUGHHAP7bmp83AGplRMWVB7u+gXs=; b=s6thDodUfmlaC+uGJBnMaZ8eZ/JEl88E+VPzE73mAN9wUMnkbyFt0RkhXmpAghR+nz/JRl U80X7xVZhgnZS4Dg== To: Peter Xu , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v4 4/7] mm/x86: Make pud_leaf() only care about PSE bit In-Reply-To: <20240807194812.819412-5-peterx@redhat.com> References: <20240807194812.819412-1-peterx@redhat.com> <20240807194812.819412-5-peterx@redhat.com> Date: Thu, 08 Aug 2024 00:22:38 +0200 Message-ID: <87bk240y8h.ffs@tglx> MIME-Version: 1.0 Content-Type: text/plain X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: James Houghton , David Hildenbrand , Dave Hansen , peterx@redhat.com, Christophe Leroy , Dave Jiang , "Aneesh Kumar K . V" , x86@kernel.org, Hugh Dickins , Matthew Wilcox , Ingo Molnar , Huang Ying , Rik van Riel , Nicholas Piggin , Borislav Petkov , "Kirill A . Shutemov" , Dan Williams , Vlastimil Babka , Oscar Salvador , linuxppc-dev@lists.ozlabs.org, Andrew Morton , Rick P Edgecombe , Mel Gorman Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Wed, Aug 07 2024 at 15:48, Peter Xu wrote: > An entry should be reported as PUD leaf even if it's PROT_NONE, in which > case PRESENT bit isn't there. I hit bad pud without this when testing dax > 1G on zapping a PROT_NONE PUD. That does not qualify as a change log. What you hit is irrelevant unless you explain the actual underlying problem. See Documentation/process/ including the TIP documentation. > diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h > index e39311a89bf4..a2a3bd4c1bda 100644 > --- a/arch/x86/include/asm/pgtable.h > +++ b/arch/x86/include/asm/pgtable.h > @@ -1078,8 +1078,7 @@ static inline pmd_t *pud_pgtable(pud_t pud) > #define pud_leaf pud_leaf > static inline bool pud_leaf(pud_t pud) > { > - return (pud_val(pud) & (_PAGE_PSE | _PAGE_PRESENT)) == > - (_PAGE_PSE | _PAGE_PRESENT); > + return pud_val(pud) & _PAGE_PSE; > } And the changelog does not explain why this change is not affecting any existing user of pud_leaf(). Thanks, tglx