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charset=us-ascii Content-Disposition: inline In-Reply-To: <20250512102242.4156463-1-ryan.roberts@arm.com> X-Stat-Signature: sjuit8xu165rwyq71wh8h6kiuj1zzhgg X-Rspam-User: X-Rspamd-Queue-Id: 38949180014 X-Rspamd-Server: rspam06 X-HE-Tag: 1747055700-321070 X-HE-Meta: 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 J64fEinn 031SW0wEwa6ukd3yXt/Og5H7WcMc2Wxnw4jSwBllEij6KzZMPgmlSPF0XMFt1KutRavHS461E182Sl2oBdttSpM6VDVw400Gk7TCX+58E26ZMqai2J3vjDAhf2RIgkCcqEAG68k5QoHss4i/67xzeiBdY6rMjbJ1Qck90qxmmc/wuyBBToD0bZQ8pYmZNyH3nYOlLNoi7GocZTLp6RxJaRH/BvHUsh+mrHpvldSTHY3Awjm+Qe3vPipAQ6i7MNbc/zCJugwog69gYPOXiO43ojVvfUNoWY6d1+9NVhzH67tAVpmsxUPYWoYalGeEyNqvlUhgnb0Py2zc3wVrJ1e8cqn1b0Yj1qT/azAUWF/1Gviz7EImBP7CjW0L4zhGKMnlyLJAKL7HMP30UYGeoam2OF+nFvgCJ3SnhbxLjmcjTC5ff42PoqQfFvkqyQTE7XaVMOY2u X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, 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, May 12, 2025 at 11:22:40AM +0100, Ryan Roberts wrote: > @@ -79,7 +83,9 @@ static inline void queue_pte_barriers(void) > #define __HAVE_ARCH_ENTER_LAZY_MMU_MODE > static inline void arch_enter_lazy_mmu_mode(void) > { > - VM_WARN_ON(in_interrupt()); > + if (in_interrupt()) > + return; > + > VM_WARN_ON(test_thread_flag(TIF_LAZY_MMU)); I still get this warning trigger with some debugging enabled (more specifically, CONFIG_DEBUG_PAGEALLOC). Patch applied on top of the arm64 for-kernelci. Is it because the unmap code uses arch_enter_lazy_mmu_mode() already and __apply_to_page_range() via __kernel_map_pages() is attempting another nested call? I think it's still safe, we just drop the optimisation in the outer code and issue the barriers immediately. So maybe drop this warning as well but add a comment on how nesting works. ------------[ cut here ]------------ WARNING: CPU: 6 PID: 1 at arch/arm64/include/asm/pgtable.h:89 __apply_to_page_range+0x85c/0x9f8 Modules linked in: ip_tables x_tables ipv6 CPU: 6 UID: 0 PID: 1 Comm: systemd Not tainted 6.15.0-rc5-00075-g676795fe9cf6 #1 PREEMPT Hardware name: QEMU KVM Virtual Machine, BIOS 2024.08-4 10/25/2024 pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : __apply_to_page_range+0x85c/0x9f8 lr : __apply_to_page_range+0x2b4/0x9f8 sp : ffff80008009b3c0 x29: ffff80008009b460 x28: ffff0000c43a3000 x27: ffff0001ff62b108 x26: ffff0000c43a4000 x25: 0000000000000001 x24: 0010000000000001 x23: ffffbf24c9c209c0 x22: ffff80008009b4d0 x21: ffffbf24c74a3b20 x20: ffff0000c43a3000 x19: ffff0001ff609d18 x18: 0000000000000001 x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000003 x14: 0000000000000028 x13: ffffbf24c97c1000 x12: ffff0000c43a3fff x11: ffffbf24cacc9a70 x10: ffff0000c43a3fff x9 : ffff0001fffff018 x8 : 0000000000000012 x7 : ffff0000c43a4000 x6 : ffff0000c43a4000 x5 : ffffbf24c9c209c0 x4 : ffff0000c43a3fff x3 : ffff0001ff609000 x2 : 0000000000000d18 x1 : ffff0000c03e8000 x0 : 0000000080000000 Call trace: __apply_to_page_range+0x85c/0x9f8 (P) apply_to_page_range+0x14/0x20 set_memory_valid+0x5c/0xd8 __kernel_map_pages+0x84/0xc0 get_page_from_freelist+0x1110/0x1340 __alloc_frozen_pages_noprof+0x114/0x1178 alloc_pages_mpol+0xb8/0x1d0 alloc_frozen_pages_noprof+0x48/0xc0 alloc_pages_noprof+0x10/0x60 get_free_pages_noprof+0x14/0x90 __tlb_remove_folio_pages_size.isra.0+0xe4/0x140 __tlb_remove_folio_pages+0x10/0x20 unmap_page_range+0xa1c/0x14c0 unmap_single_vma.isra.0+0x48/0x90 unmap_vmas+0xe0/0x200 vms_clear_ptes+0xf4/0x140 vms_complete_munmap_vmas+0x7c/0x208 do_vmi_align_munmap+0x180/0x1a8 do_vmi_munmap+0xac/0x188 __vm_munmap+0xe0/0x1e0 __arm64_sys_munmap+0x20/0x38 invoke_syscall+0x48/0x104 el0_svc_common.constprop.0+0x40/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x4c/0x16c el0t_64_sync_handler+0x10c/0x140 el0t_64_sync+0x198/0x19c irq event stamp: 281312 hardirqs last enabled at (281311): [] bad_range+0x164/0x1c0 hardirqs last disabled at (281312): [] el1_dbg+0x24/0x98 softirqs last enabled at (281054): [] handle_softirqs+0x4cc/0x518 softirqs last disabled at (281019): [] __do_softirq+0x14/0x20 ---[ end trace 0000000000000000 ]--- -- Catalin