Hi all, While fuzzing with trinity inside a KVM tools guest running latest -next, I've noticed that quite often there's a hang happening inside shmem_fallocate. There are several processes stuck trying to acquire inode->i_mutex (for more than 2 minutes), while the process that holds it has the following stack trace: [ 2059.561282] Call Trace: [ 2059.561557] [<ffffffff81175588>] ? sched_clock_cpu+0x108/0x120 [ 2059.562444] [<ffffffff8118e1fa>] ? get_lock_stats+0x2a/0x60 [ 2059.563247] [<ffffffff8118e23e>] ? put_lock_stats+0xe/0x30 [ 2059.563930] [<ffffffff8118e1fa>] ? get_lock_stats+0x2a/0x60 [ 2059.564646] [<ffffffff810adc13>] ? x2apic_send_IPI_mask+0x13/0x20 [ 2059.565431] [<ffffffff811b3224>] ? __rcu_read_unlock+0x44/0xb0 [ 2059.566161] [<ffffffff811d48d5>] ? generic_exec_single+0x55/0x80 [ 2059.566992] [<ffffffff8128bd45>] ? page_remove_rmap+0x295/0x320 [ 2059.567782] [<ffffffff843afe8c>] ? _raw_spin_lock+0x6c/0x80 [ 2059.568390] [<ffffffff8127c6cc>] ? zap_pte_range+0xec/0x590 [ 2059.569157] [<ffffffff8127c8d0>] ? zap_pte_range+0x2f0/0x590 [ 2059.569907] [<ffffffff810c6560>] ? flush_tlb_mm_range+0x360/0x360 [ 2059.570855] [<ffffffff843aa863>] ? preempt_schedule+0x53/0x80 [ 2059.571613] [<ffffffff81077086>] ? ___preempt_schedule+0x56/0xb0 [ 2059.572526] [<ffffffff810c6536>] ? flush_tlb_mm_range+0x336/0x360 [ 2059.573368] [<ffffffff8127a6eb>] ? tlb_flush_mmu+0x3b/0x90 [ 2059.574152] [<ffffffff8127a754>] ? tlb_finish_mmu+0x14/0x40 [ 2059.574951] [<ffffffff8127d276>] ? zap_page_range_single+0x146/0x160 [ 2059.575797] [<ffffffff81193768>] ? trace_hardirqs_on+0x8/0x10 [ 2059.576629] [<ffffffff8127d303>] ? unmap_mapping_range+0x73/0x180 [ 2059.577362] [<ffffffff8127d38e>] ? unmap_mapping_range+0xfe/0x180 [ 2059.578194] [<ffffffff8125eeb7>] ? truncate_inode_page+0x37/0x90 [ 2059.579013] [<ffffffff8126bc61>] ? shmem_undo_range+0x711/0x830 [ 2059.579807] [<ffffffff8127d3f8>] ? unmap_mapping_range+0x168/0x180 [ 2059.580729] [<ffffffff8126bd98>] ? shmem_truncate_range+0x18/0x40 [ 2059.581598] [<ffffffff8126c0a9>] ? shmem_fallocate+0x99/0x2f0 [ 2059.582325] [<ffffffff81278eae>] ? madvise_vma+0xde/0x1c0 [ 2059.583049] [<ffffffff8119555a>] ? __lock_release+0x1da/0x1f0 [ 2059.583816] [<ffffffff812d0cb6>] ? do_fallocate+0x126/0x170 [ 2059.584581] [<ffffffff81278ec4>] ? madvise_vma+0xf4/0x1c0 [ 2059.585302] [<ffffffff81279118>] ? SyS_madvise+0x188/0x250 [ 2059.586012] [<ffffffff843ba5d0>] ? tracesys+0xdd/0xe2 [ 2059.586689] ffff880f39bc3db8 0000000000000002 ffff880fce4b0000 ffff880fce4b0000 [ 2059.587768] ffff880f39bc2010 00000000001d78c0 00000000001d78c0 00000000001d78c0 [ 2059.588840] ffff880fce6a0000 ffff880fce4b0000 ffff880fe5bd6d40 ffff880fa88e8ab0 Thanks, Sasha -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>