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Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:52158) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1vP1qZ-0000000071m-1bEl; Fri, 28 Nov 2025 17:01:27 +0000 Received: from linux by shell.armlinux.org.uk with local (Exim 4.98.2) (envelope-from ) id 1vP1qR-000000003mj-01ZK; Fri, 28 Nov 2025 17:01:19 +0000 Date: Fri, 28 Nov 2025 17:01:18 +0000 From: "Russell King (Oracle)" To: Sebastian Andrzej Siewior Cc: Xie Yuanbin , akpm@linux-foundation.org, arnd@arndb.de, brauner@kernel.org, david.laight@runbox.com, hch@lst.de, jack@suse.com, kuninori.morimoto.gx@renesas.com, liaohua4@huawei.com, lilinjie8@huawei.com, linux-arm-kernel@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, lorenzo.stoakes@oracle.com, marc.zyngier@arm.com, nico@fluxnic.net, pangliyuan1@huawei.com, pfalcato@suse.de, punitagrawal@gmail.com, rjw@rjwysocki.net, rppt@kernel.org, tony@atomide.com, vbabka@suse.cz, viro@zeniv.linux.org.uk, wangkefeng.wang@huawei.com, will@kernel.org, wozizhi@huaweicloud.com Subject: Re: [RFC PATCH v2 1/2] ARM/mm/fault: always goto bad_area when handling with page faults of kernel address Message-ID: References: <20251127145127.qUXs_UAE@linutronix.de> <20251128022756.9973-1-xieyuanbin1@huawei.com> <20251128120359.Xc09qn1W@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251128120359.Xc09qn1W@linutronix.de> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251128_090229_048706_315B1F0C X-CRM114-Status: GOOD ( 15.92 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Nov 28, 2025 at 01:03:59PM +0100, Sebastian Andrzej Siewior wrote: > On 2025-11-28 10:27:56 [+0800], Xie Yuanbin wrote: > > According to the discussion, it might be better to handle the kernel > > address fault directly, just like what x86 does, instead of finding VMA. > > the kernel fault shouldn't have a VMA > > > Link: https://elixir.bootlin.com/linux/v6.18-rc7/source/arch/x86/mm/fault.c#L1473 > > ```c > > if (unlikely(fault_in_kernel_space(address))) > > do_kern_addr_fault(regs, error_code, address); > > else > > do_user_addr_fault(regs, error_code, address); > > ``` > > > > It seems your patches hasn't been merged into the linux-next branch yet. > > I hope Russell will add them once he gets to it. They got reviewed, I > added them to the patch system. I'm not sure which patches you're talking about, but discussion is still ongoing, so it would be greatly premature to merge anything. https://lore.kernel.org/r/aSmUnZZATTn3JD7m@willie-the-truck There are now many threads each with their own discussion, which makes it more difficult to work out which is the implementation that should be merged. Clearly, not everyone knows about the other discussion threads. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!