On Tue, Jun 04, 2024 at 10:41:40AM -0700, Sidhartha Kumar wrote: > Use mas->store_type to simplify the logic of identifying the type of > write. > > Signed-off-by: Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx> > --- > lib/maple_tree.c | 6 ++---- > 1 file changed, 2 insertions(+), 4 deletions(-) > > diff --git a/lib/maple_tree.c b/lib/maple_tree.c > index 314691fd1c67..faadddbe2086 100644 > --- a/lib/maple_tree.c > +++ b/lib/maple_tree.c > @@ -3437,12 +3437,10 @@ static noinline_for_kasan int mas_commit_b_node(struct ma_wr_state *wr_mas, > enum maple_type b_type = b_node->type; > > old_enode = wr_mas->mas->node; > - if ((b_end < mt_min_slots[b_type]) && > - (!mte_is_root(old_enode)) && > - (mas_mt_height(wr_mas->mas) > 1)) > + if (wr_mas->mas->store_type == wr_rebalance) > return mas_rebalance(wr_mas->mas, b_node); > > - if (b_end >= mt_slots[b_type]) > + if (wr_mas->mas->store_type == wr_split_store) > return mas_split(wr_mas->mas, b_node); > > if (mas_reuse_node(wr_mas, b_node, end)) This reliably results in "kernel BUG at mm/mmap.c:3412!". bt below reliably reproduces as follows: spawn "perf top", hit enter twice to disassemble a func. tui hangs indefinitely, console shows the splat below. I verified going one commit down produces a working kernel. kernel BUG at mm/mmap.c:3412! [ 35.820042] Oops: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI [ 35.821101] CPU: 4 PID: 1066 Comm: perf-top-UI Tainted: G W 6.10.0-rc5-00304-g30e5748b1d44 #155 [ 35.822929] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.1-0-g3208b098f51a-prebuilt.qemu.org 04/01/2014 [ 35.824957] RIP: 0010:exit_mmap+0x392/0x3a0 [ 35.825794] Code: ef e8 02 9f fe ff eb d7 be 01 00 00 00 48 89 ef e8 73 a3 fe ff eb be 31 f6 48 89 ef e8 a7 a2 fe ff eb a8 0f 0b e9 75 fe ff ff <0f> 0b e8 a7 b2 c1 00 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 [ 35.829141] RSP: 0018:ff7fe6c8c2393c40 EFLAGS: 00010293 [ 35.830103] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 35.831398] RDX: ff39fe34499c3c00 RSI: 0000000000000001 RDI: ff39fe34499c3c08 [ 35.832705] RBP: ff39fe3441a28580 R08: 000000000000000c R09: 0000000000000060 [ 35.834010] R10: ff39fe3450ad5600 R11: 0000000000000000 R12: 00000000000000e8 [ 35.835295] R13: 0000000000003593 R14: ff39fe3441a28628 R15: ff39fe3441a285c0 [ 35.836569] FS: 0000000000000000(0000) GS:ff39fe39a7700000(0000) knlGS:0000000000000000 [ 35.838042] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 35.839093] CR2: 00007efd624f39ed CR3: 000000010130e001 CR4: 0000000000371ef0 [ 35.840389] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 35.841892] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400 [ 35.843182] Call Trace: [ 35.843646] <TASK> [ 35.844051] ? die+0x36/0x90 [ 35.844602] ? do_trap+0xdd/0x100 [ 35.845226] ? exit_mmap+0x392/0x3a0 [ 35.845915] ? do_error_trap+0x65/0x80 [ 35.846614] ? exit_mmap+0x392/0x3a0 [ 35.847287] ? exc_invalid_op+0x50/0x70 [ 35.847999] ? exit_mmap+0x392/0x3a0 [ 35.848662] ? asm_exc_invalid_op+0x1a/0x20 [ 35.849437] ? exit_mmap+0x392/0x3a0 [ 35.850120] __mmput+0x3d/0x130 [ 35.850713] begin_new_exec+0x4ed/0xb00 [ 35.851428] ? load_elf_phdrs+0x6c/0xc0 [ 35.852150] load_elf_binary+0x2ca/0x15a0 [ 35.852890] ? __kernel_read+0x1d8/0x2f0 [ 35.853621] ? __kernel_read+0x1d8/0x2f0 [ 35.854348] ? load_misc_binary+0x1f6/0x310 [ 35.855113] bprm_execve+0x243/0x600 [ 35.855784] do_execveat_common.isra.0+0x1bd/0x220 [ 35.856672] __x64_sys_execve+0x36/0x40 [ 35.857384] do_syscall_64+0x52/0x150 [ 35.858088] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 35.859014] RIP: 0033:0x7efd624f3a17 [ 35.859677] Code: Unable to access opcode bytes at 0x7efd624f39ed. [ 35.860790] RSP: 002b:00007efd48bf8dc8 EFLAGS: 00000202 ORIG_RAX: 000000000000003b [ 35.862170] RAX: ffffffffffffffda RBX: 000055e5736a44e3 RCX: 00007efd624f3a17 [ 35.863472] RDX: 000055e59c315000 RSI: 00007efd48bf9050 RDI: 000055e5736a44e3 [ 35.864768] RBP: 00007efd48bf8e40 R08: 0000000000000000 R09: 00007efd48c006c0 [ 35.866475] R10: 00007efd62430e50 R11: 0000000000000202 R12: 00007efd48bf9050 [ 35.868167] R13: 000055e59c315000 R14: 0000000000000001 R15: 0000000000000001 [ 35.869873] </TASK> [ 35.870676] Modules linked in: [ 35.871944] ---[ end trace 0000000000000000 ]---
