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charset=UTF-8 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260923_014324_887222_9BDD87E4 X-CRM114-Status: UNSURE ( 7.09 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-um@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-um" Errors-To: linux-um-bounces+linux-um=archiver.kernel.org@lists.infradead.org On Tue, Sep 22, 2026 at 04:35:36PM +0100, Lorenzo Stoakes (ARM) wrote: >Each of these architectures directly free page tables without routing these >changes through tlb_remove_ptdesc(). > >The use of tlb_remove_ptdesc() is required for >CONFIG_MMU_GATHER_RCU_TABLE_FREE to correctly free page tables under RCU, >so simply update these architectures to use these functions. > >Since none of the architectures share page tables or do anything unusual, >nothing complicated is required here. > >Therefore this is simply a mechanical change - convert __pud_free_tlb(), >__pmd_free_tlb() and __pte_free_tlb() to use tlb_remove_ptdesc() as >required. > >At the point this is in place, all mmu_gather page table freeing is >performed under RCU, and thus MMU_GATHER_RCU_TABLE_FREE is selected for >each architecture. > >Note that CONFIG_MMU_GATHER_RCU_TABLE_FREE is dependent on CONFIG_MMU for >xtensa to reflect the fact that nommu does not implement page table >gathering. > >This forms part of an overall effort to switch every architecture to this >mode. > >Acked-by: Kiryl Shutsemau (Meta) >Signed-off-by: Lorenzo Stoakes (ARM) >--- Right, the old frees already end up in pagetable_dtor_free(). With tlb_remove_ptdesc(), the same cleanup happens after an RCU grace period. Makes sense to me, feel free to add: Acked-by: Lance Yang