From nobody Sat Jun 13 00:39:22 2026 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 6007641C2FD; Mon, 11 May 2026 18:27:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778524061; cv=none; b=a2LYyTAPoUzODB8yligwpbMVzDqxxKwJKOFhDSr+h83N3NPuDsnq2s6wQ6uAUQtV6l/E2GEwMY94QOajfL24d2C2Z3hJ9oAqi18bEbweywR1TnUctL6kl7QL69FB9TTpDzjm+v6aJDPIyBUjxroVD4luC5auSvIxbaxYiMuB20g= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778524061; c=relaxed/simple; bh=65nI++BFOyBbi36c+0xYOnLcdpS6h9QqFTzC/aFXB7U=; h=Date:From:To:Subject:Cc:In-Reply-To:References:MIME-Version: Message-ID:Content-Type; b=FGo+6ynVS626fiVsYJeybPrfMNKJefYNz/noilcAgB+WAFw/FV/sFsp2fJvSsNguVdytiU/F1A63dhJTPZAufAGsbrT0Mlp0F28yO34JCtsyGEqldiRaxWypoJ4Xm+kXmQJPeK6a3z+BOtySLF9hEncBXD4AmdCCHbM7/JkdxrI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=Wj9x0avN; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=wVXmCvJS; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="Wj9x0avN"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="wVXmCvJS" Date: Mon, 11 May 2026 18:27:31 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1778524053; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=3lFX5Rig6LqPSxRx0pvA1WSJAwuttYuEQFiFvJMcQTg=; b=Wj9x0avNQH259/0V5qydF2nRBsSrMofHpyhw9NcUQdC4y/IN1XbydoyRAVF1pi/gdPo9o/ 2To8zkthPqi27O00rBWIZtV+PkXty+J820CfceMXNIQM2IhCALkzGWPU9hlhpT3hQ4f+H3 S+wggdr2L57WNyioZjgEqKxQKzOrQN74DYqd1NSkR9pS43/k8WmRutuFvGDtPtnzRlrR97 3RQHfN6zhZ4fsBPxNY2h2K54l7lYSWazHSl0Cae9irLmuy1yG2hLPoQyLkObVUlMn0z9zN J8ikMHkCXj/GWZXrOo1j1pJvJO5FG7B4YRVwAvzsz3xLpb1Ia7MqKhzOPS1YRw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1778524053; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=3lFX5Rig6LqPSxRx0pvA1WSJAwuttYuEQFiFvJMcQTg=; b=wVXmCvJSWg3IpkO+o4ozS1PFhaqpfndeCylYSeh0CHbCfX2G4Bp6cLR/MINqIg+rREx+g3 JWyFei0D0pBvA4Dg== From: "tip-bot2 for Brendan Jackman" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: x86/mm] x86: Update comment about pgd_list Cc: Brendan Jackman , Dave Hansen , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20260323-pgd_list-comment-v2-1-77ccf2dc77e8@google.com> References: <20260323-pgd_list-comment-v2-1-77ccf2dc77e8@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-ID: <177852405161.188840.12869958344226610704.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Precedence: bulk Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable The following commit has been merged into the x86/mm branch of tip: Commit-ID: 952ac097ce98901c608cdced012f89a90367401e Gitweb: https://git.kernel.org/tip/952ac097ce98901c608cdced012f89a90= 367401e Author: Brendan Jackman AuthorDate: Mon, 23 Mar 2026 14:25:07=20 Committer: Dave Hansen CommitterDate: Mon, 11 May 2026 11:26:33 -07:00 x86: Update comment about pgd_list This venerable comment got detached from its context when the code moved in commit 394158559d4c ("x86: move all the pgd_list handling to one place"). Put it back next to its context. It was originally on pgd_list_add() but it actually describes pgd_list so put it there. While moving it, update it to strip away stale and superfluous info. pageattr.c doesn't exist any more. pgd_list is now required for all x86 architectures. Also be slightly more precise about what PGDs are in this list. [ dhansen: tweak and trim the updated comment a bit ] Signed-off-by: Brendan Jackman Signed-off-by: Dave Hansen Link: https://patch.msgid.link/20260323-pgd_list-comment-v2-1-77ccf2dc77e8@= google.com --- arch/x86/mm/fault.c | 5 +++++ arch/x86/mm/pgtable.c | 11 ----------- 2 files changed, 5 insertions(+), 11 deletions(-) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 63de8e8..250942e 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -169,6 +169,11 @@ is_prefetch(struct pt_regs *regs, unsigned long error_= code, unsigned long addr) } =20 DEFINE_SPINLOCK(pgd_lock); +/* + * List of all process' PGD pages (excluding init_mm and some other special + * system-wide PGDs). Mainly used to keep the kernel portion of the address + * space in sync across mms. + */ LIST_HEAD(pgd_list); =20 #ifdef CONFIG_X86_32 diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index da7f0a0..f32facd 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -99,17 +99,6 @@ static void pgd_dtor(pgd_t *pgd) spin_unlock(&pgd_lock); } =20 -/* - * List of all pgd's needed for non-PAE so it can invalidate entries - * in both cached and uncached pgd's; not needed for PAE since the - * kernel pmd is shared. If PAE were not to share the pmd a similar - * tactic would be needed. This is essentially codepath-based locking - * against pageattr.c; it is the unique case in which a valid change - * of kernel pagetables can't be lazily synchronized by vmalloc faults. - * vmalloc faults work because attached pagetables are never freed. - * -- nyc - */ - #ifdef CONFIG_X86_PAE /* * In PAE mode, we need to do a cr3 reload (=3Dtlb flush) when