This reverts commit e47110e90584a22e9980510b00d0dfad3a83354e. While I was doing zram testing, I found sometimes decompression failed since the compression buffer was corrupted. With investigation, I found below commit calls cond_resched unconditionally so it could make a problem in atomic context if the task is reschedule. Revert the original commit for now. [ 55.109012] BUG: sleeping function called from invalid context at mm/vmalloc.c:108^M [ 55.110774] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 946, name: memhog^M [ 55.111973] 3 locks held by memhog/946:^M [ 55.112807] #0: ffff9d01d4b193e8 (&mm->mmap_lock#2){++++}-{4:4}, at: __mm_populate+0x103/0x160^M [ 55.114151] #1: ffffffffa3d53de0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath.constprop.0+0xa98/0x1160^M [ 55.115848] #2: ffff9d01d56b8110 (&zspage->lock){.+.+}-{3:3}, at: zs_map_object+0x8e/0x1f0^M [ 55.118947] CPU: 0 PID: 946 Comm: memhog Not tainted 5.9.3-00011-gc5bfc0287345-dirty #316^M [ 55.121265] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1 04/01/2014^M [ 55.122540] Call Trace:^M [ 55.122974] dump_stack+0x8b/0xb8^M [ 55.123588] ___might_sleep.cold+0xb6/0xc6^M [ 55.124328] unmap_kernel_range_noflush+0x2eb/0x350^M [ 55.125198] unmap_kernel_range+0x14/0x30^M [ 55.125920] zs_unmap_object+0xd5/0xe0^M [ 55.126604] zram_bvec_rw.isra.0+0x38c/0x8e0^M [ 55.127462] zram_rw_page+0x90/0x101^M [ 55.128199] bdev_write_page+0x92/0xe0^M [ 55.128957] ? swap_slot_free_notify+0xb0/0xb0^M [ 55.129841] __swap_writepage+0x94/0x4a0^M [ 55.130636] ? do_raw_spin_unlock+0x4b/0xa0^M [ 55.131462] ? _raw_spin_unlock+0x1f/0x30^M [ 55.132261] ? page_swapcount+0x6c/0x90^M [ 55.133038] pageout+0xe3/0x3a0^M [ 55.133702] shrink_page_list+0xb94/0xd60^M [ 55.134626] shrink_inactive_list+0x158/0x460^M Cc: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx> Cc: Harish Sriram <harish@xxxxxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Minchan Kim <minchan@xxxxxxxxxx> --- mm/vmalloc.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 6ae491a8b210..a4f1d39ce710 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -102,8 +102,6 @@ static void vunmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end, if (pmd_none_or_clear_bad(pmd)) continue; vunmap_pte_range(pmd, addr, next, mask); - - cond_resched(); } while (pmd++, addr = next, addr != end); } -- 2.29.1.341.ge80a0c044ae-goog