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charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 3538716000B X-Stat-Signature: tzhgb6sztxtfdjup187jaxhsmergtyfp X-Rspam-User: X-HE-Tag: 1739207006-401329 X-HE-Meta: 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 vX2ePw3b 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000067, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, Feb 10, 2025 at 05:49:38PM +0100, Ezra Buehler wrote: > When running vanilla Linux 6.13 or newer (6.14-rc2) on the > AT91SAM9G25-based GARDENA smart Gateway, we are seeing a NULL pointer > dereference resulting in a kernel panic. The culprit seems to be commit > fc9c45b71f43 ("arm: adjust_pte() usepte_offset_map_rw_nolock()"). > Reverting the commit apparently fixes the issue. The blamed commit is buggy: arch/arm/include/asm/tlbflush.h: #define update_mmu_cache(vma, addr, ptep) \ update_mmu_cache_range(NULL, vma, addr, ptep, 1) So vmf can be NULL. This didn't used to matter before this commit, because vmf was not used by ARM's update_mmu_cache_range(). However, the commit introduced a dereference of it, which now causes a NULL point dereference. Not sure what the correct solution is, but at a guess, both: if (ptl != vmf->ptl) need to become: if (!vmf || ptl != vmf->ptl) but I haven't checked wha tthe locking context actually is here (I've been out of MM stuff too long to know this off the top of my head.) -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!