From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f175.google.com (mail-pf1-f175.google.com [209.85.210.175]) (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 2B8671D31B5; Tue, 10 Dec 2024 03:59:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.175 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733803156; cv=none; b=E67Iwc+1Sh+G7pw33F4KFHxZRZ7pyPE3Cu/RHrk9TxUYtgHnZPSQhWgQk7jYRzEpDLJVz1HaBIiX7V6XmnneOn83YfTOBapQYdcvTBqJlVm3CHDxd3pc/rLYFDbtfmqK3vwql3TregZUkLO8sm3kQCwvvMJN1d91bmrVSrJ49uk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733803156; c=relaxed/simple; bh=EfORchtwnv7KmnN/gELMeKzTjGN3v+5Zf9FNg5xJ5MQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=lFoe4MXbeOsAwwDZgYx9Z0j3AFtSwXt6BMCTcRwpkNOXhIS5aZFIpZPOxjxNxfU/ueNPLM5tbGQQSSUJ1F7BwSCE5RAjdKnykO2ZZzLkImCMzfhmDoq0vguZD2qCO2hH5B0lW47cq/Fiw0rh9mP6Bf+k5KRrYPqHIbr1tRKZtqg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=kernel.org; spf=pass smtp.mailfrom=gmail.com; arc=none smtp.client-ip=209.85.210.175 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=kernel.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-pf1-f175.google.com with SMTP id d2e1a72fcca58-725f4025e25so1175868b3a.1; Mon, 09 Dec 2024 19:59:14 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1733803154; x=1734407954; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=uZdH4tcmxivh4QDFce0d2NRScLtiuHUjaYwYxPLsFgg=; b=YatOcGn6cijC95Uio+v8hNwv1VeEeQ3y6sYpoZ6q1FKXynsJ9st510RmW6Vdf8nAIC RZS4IW4VtLbSPL/u1s3PYY2ae6091cCsC1s7T2XO6guH5QaJR9YKLOJOmAeA6lXEtyJx iy45zR+nymkBrme2l4hBkrUnhktmo8indGrighMQ8KZoaRYOwTcmu4J3G8Bm+av9c7Sd pv+IhGXzhjlhoqupKZrDi1X1O3zH/ZQo7WI3rj2yu505TJiLWFdB1dXR/bk+OT4i50Tg KOZvmURs+uiHUUV34o7+zk2mgp91aSBQyuWV2sio0PgEoIlC/Q8TpzWVX9eR7YMjWtmj JfeA== X-Forwarded-Encrypted: i=1; AJvYcCUMnjsO/BTQWODCY6VW39lyA2pTLJ6PYSO4ItGocG8u0M7Cxbe7JNlZqFUeQiU1aJwyvx1e5gwLZ0hx@vger.kernel.org, AJvYcCVZRhuHbCytWdVc3wZKZ8hEAnMZib1YZ/tXoT/X02AGuqd33d4ibVBsJiX0WmaUMBVcPkd429qG5dy/3NZHnxE=@vger.kernel.org, AJvYcCWxEKTUpNTY5eL4iDvQ4ST5sWkq9mnPLTEMaLI659ac1s0pXSBgRm3BIhJcv1uDdOWj4ss6YE7e@vger.kernel.org, AJvYcCXjYr8f24s9SEtJreW5NzNd5qpHYO0RqLVEbefR7KYTo+ycssbA6HBy1eQqqdZy006TofudCkpqradRUmDk@vger.kernel.org X-Gm-Message-State: AOJu0YxggFdKkRVuhgFoFID+LW4GrKSRlg2/iHHzbzmlVpKX50AJ0hDe Cz0rrEAeMhftE08odxatWeEHJ9D6GrihNLVO+JbdBUhkWOLljsR6 X-Gm-Gg: ASbGncuqQvd+SfqqTWIBfYDH8DNsZmeqVTfoT1JwwddY0EwgidaZwD3iCvjOf+SHOj5 LVkfY8JwTuOokQ88pQdrjnklLNK7pxVkbUm5tHpfuDIixEuu7LvythAYNm9qJEzyyj2U15NYoHb 454mZPWHOML87o6QAtYf+QKVa/52ipGgHkEws7nu2DehxoFTAowmdHZAZzDGU33+t6pcowKrZXC NbgWDVVSlO8e51aoamXcgkfusC97nqWqLMCScIqqN8yBFrAQKaJN4IXTkNtPqzNdA4lL8zXbhwM P/i8BvAtf/fwqTjRcb92/w== X-Google-Smtp-Source: AGHT+IFLYl8oqU728VFGIiHD6jjP0ttkMIa5bvlvQdGUuldgwTreeyu+gObx0DLr0uZOxz9WXJqBCQ== X-Received: by 2002:a05:6a00:1c85:b0:727:3b77:417c with SMTP id d2e1a72fcca58-7273b774407mr5601322b3a.20.1733803154288; Mon, 09 Dec 2024 19:59:14 -0800 (PST) Received: from V92F7Y9K0C (c-73-162-198-50.hsd1.ca.comcast.net. [73.162.198.50]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-725c91baf30sm5510482b3a.80.2024.12.09.19.59.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 09 Dec 2024 19:59:13 -0800 (PST) Date: Mon, 9 Dec 2024 19:59:10 -0800 From: Dennis Zhou To: Uros Bizjak Cc: x86@kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-bcachefs@vger.kernel.org, linux-arch@vger.kernel.org, netdev@vger.kernel.org, Thomas Gleixner , Tejun Heo , Christoph Lameter , Linus Torvalds , Andy Lutomirski , Ingo Molnar , Nadav Amit , Brian Gerst , Dan Carpenter , "H . Peter Anvin" , Peter Zijlstra Subject: Re: [PATCH v3 0/6] Enable strict percpu address space checks Message-ID: References: <20241208204708.3742696-1-ubizjak@gmail.com> Precedence: bulk X-Mailing-List: linux-arch@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241208204708.3742696-1-ubizjak@gmail.com> Hi Uros, On Sun, Dec 08, 2024 at 09:45:15PM +0100, Uros Bizjak wrote: > Enable strict percpu address space checks via x86 named address space > qualifiers. Percpu variables are declared in __seg_gs/__seg_fs named > AS and kept named AS qualified until they are dereferenced via percpu > accessor. This approach enables various compiler checks for > cross-namespace variable assignments. > > Please note that current version of sparse doesn't know anything about > __typeof_unqual__() operator. Avoid the usage of __typeof_unqual__() > when sparse checking is active to prevent sparse errors with unknowing > keyword. The proposed patch by Dan Carpenter to implement > __typeof_unqual__() handling in sparse is located at: > > https://lore.kernel.org/lkml/5b8d0dee-8fb6-45af-ba6c-7f74aff9a4b8@stanley.mountain/ > > v2: - Add comment to remove test for __CHECKER__ once sparse learns > about __typeof_unqual__. > - Add Acked-by: tags. > v3: - Rename __per_cpu_qual to __percpu_qual. > - Add more Acked-by: tags. > > Cc: Thomas Gleixner > Cc: Dennis Zhou > Cc: Tejun Heo > Cc: Christoph Lameter > Cc: Linus Torvalds > Cc: Andy Lutomirski > Cc: Ingo Molnar > Cc: Nadav Amit > Cc: Brian Gerst > Cc: Dan Carpenter > Cc: H. Peter Anvin > Cc: Peter Zijlstra > > Uros Bizjak (6): > x86/kgdb: Use IS_ERR_PCPU() macro > compiler.h: Introduce TYPEOF_UNQUAL() macro > percpu: Use TYPEOF_UNQUAL() in variable declarations > percpu: Use TYPEOF_UNQUAL() in *_cpu_ptr() accessors > percpu: Repurpose __percpu tag as a named address space qualifier > percpu/x86: Enable strict percpu checks via named AS qualifiers > > arch/x86/include/asm/percpu.h | 38 ++++++++++++++++++++++++--------- > arch/x86/kernel/kgdb.c | 2 +- > fs/bcachefs/util.h | 2 +- > include/asm-generic/percpu.h | 39 ++++++++++++++++++++++------------ > include/linux/compiler.h | 13 ++++++++++++ > include/linux/compiler_types.h | 2 +- > include/linux/part_stat.h | 2 +- > include/linux/percpu-defs.h | 6 +++--- > include/net/snmp.h | 5 ++--- > init/Kconfig | 3 +++ > kernel/locking/percpu-rwsem.c | 2 +- > net/mpls/internal.h | 4 ++-- > 12 files changed, 82 insertions(+), 36 deletions(-) > > -- > 2.42.0 > This all looks good to me. Acked-by: Dennis Zhou Thanks, Dennis