On 9/27/19 4:15 AM, Andrew Morton wrote:
On Thu, 26 Sep 2019 17:55:51 +0530 "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxx> wrote:With altmap, all the resource pfns are not initialized. While initializing pfn, altmap reserve space is skipped. Hence when removing pfn from zone skip pfns that were never initialized. Update memunmap_pages to calculate start and end pfn based on altmap values. This fixes a kernel crash that is observed when destroying namespace. [ 74.745056] BUG: Unable to handle kernel data access at 0xc00c000001400000 [ 74.745256] Faulting instruction address: 0xc0000000000b58b0 cpu 0x2: Vector: 300 (Data Access) at [c00000026ea93580] pc: c0000000000b58b0: memset+0x68/0x104 lr: c0000000003eb008: page_init_poison+0x38/0x50 ... current = 0xc000000271c67d80 paca = 0xc00000003fffd680 irqmask: 0x03 irq_happened: 0x01 pid = 3665, comm = ndctl [link register ] c0000000003eb008 page_init_poison+0x38/0x50 [c00000026ea93830] c0000000004754d4 remove_pfn_range_from_zone+0x64/0x3e0 [c00000026ea938a0] c0000000004b8a60 memunmap_pages+0x300/0x400 [c00000026ea93930] c0000000009e32a0 devm_action_release+0x30/0x50Doesn't apply to mainline or -next. Which tree is this against?
After applying the patches from David on mainline. That is the reason I replied to this thread. I should have mentioned in the email that it is based on patch series "[PATCH v4 0/8] mm/memory_hotplug: Shrink zones before removing memory"
-aneesh
