From b831306b3b7d9202b300f7f6ec32f5be2b4926a3 Mon Sep 17 00:00:00 2001 From: David Sterba Date: Wed, 3 May 2023 21:08:16 +0200 Subject: [PATCH] btrfs: print assertion failure report and stack trace from the same line Assertions reports are split into two parts, the exact file and location of the condition and then the stack trace printed from btrfs_assertfail(). This means all the stack traces report the same line and this is what's typically reported by various tools, making it harder to distinguish the reports. [403.2467] assertion failed: refcount_read(&block_group->refs) == 1, in fs/btrfs/block-group.c:4259 [403.2479] ------------[ cut here ]------------ [403.2484] kernel BUG at fs/btrfs/messages.c:259! [403.2488] invalid opcode: 0000 [#1] PREEMPT SMP KASAN [403.2493] CPU: 2 PID: 23202 Comm: umount Not tainted 6.2.0-rc4-default+ #67 [403.2499] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552-rebuilt.opensuse.org 04/01/2014 [403.2509] RIP: 0010:btrfs_assertfail+0x19/0x1b [btrfs] ... [403.2595] Call Trace: [403.2598] [403.2601] btrfs_free_block_groups.cold+0x52/0xae [btrfs] [403.2608] close_ctree+0x6c2/0x761 [btrfs] [403.2613] ? __wait_for_common+0x2b8/0x360 [403.2618] ? btrfs_cleanup_one_transaction.cold+0x7a/0x7a [btrfs] [403.2626] ? mark_held_locks+0x6b/0x90 [403.2630] ? lockdep_hardirqs_on_prepare+0x13d/0x200 [403.2636] ? __call_rcu_common.constprop.0+0x1ea/0x3d0 [403.2642] ? trace_hardirqs_on+0x2d/0x110 [403.2646] ? __call_rcu_common.constprop.0+0x1ea/0x3d0 [403.2652] generic_shutdown_super+0xb0/0x1c0 [403.2657] kill_anon_super+0x1e/0x40 [403.2662] btrfs_kill_super+0x25/0x30 [btrfs] [403.2668] deactivate_locked_super+0x4c/0xc0 By making btrfs_assertfail a macro we'll get the same line number for the BUG output: [63.5736] assertion failed: 0, in fs/btrfs/super.c:1572 [63.5758] ------------[ cut here ]------------ [63.5782] kernel BUG at fs/btrfs/super.c:1572! [63.5807] invalid opcode: 0000 [#2] PREEMPT SMP KASAN [63.5831] CPU: 0 PID: 859 Comm: mount Tainted: G D 6.3.0-rc7-default+ #2062 [63.5868] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a-rebuilt.opensuse.org 04/01/2014 [63.5905] RIP: 0010:btrfs_mount+0x24/0x30 [btrfs] [63.5964] RSP: 0018:ffff88800e69fcd8 EFLAGS: 00010246 [63.5982] RAX: 000000000000002d RBX: ffff888008fc1400 RCX: 0000000000000000 [63.6004] RDX: 0000000000000000 RSI: ffffffffb90fd868 RDI: ffffffffbcc3ff20 [63.6026] RBP: ffffffffc081b200 R08: 0000000000000001 R09: ffff88800e69fa27 [63.6046] R10: ffffed1001cd3f44 R11: 0000000000000001 R12: ffff888005a3c370 [63.6062] R13: ffffffffc058e830 R14: 0000000000000000 R15: 00000000ffffffff [63.6081] FS: 00007f7b3561f800(0000) GS:ffff88806c600000(0000) knlGS:0000000000000000 [63.6105] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [63.6120] CR2: 00007fff83726e10 CR3: 0000000002a9e000 CR4: 00000000000006b0 [63.6137] Call Trace: [63.6143] [63.6148] legacy_get_tree+0x80/0xd0 [63.6158] vfs_get_tree+0x43/0x120 [63.6166] do_new_mount+0x1f3/0x3d0 [63.6176] ? do_add_mount+0x140/0x140 [63.6187] ? cap_capable+0xa4/0xe0 [63.6197] path_mount+0x223/0xc10 This comes at a cost of bloating the final btrfs.ko module due all the inlining, as long as assertions are compiled in. This is a must for debugging builds but this is often enabled on release builds too. Release build: text data bss dec hex filename 1251676 20317 16088 1288081 13a791 pre/btrfs.ko 1260612 29473 16088 1306173 13ee3d post/btrfs.ko DELTA: +8936 CC: Josh Poimboeuf Signed-off-by: David Sterba --- fs/btrfs/messages.c | 8 -------- fs/btrfs/messages.h | 8 +++++++- tools/objtool/check.c | 1 - 3 files changed, 7 insertions(+), 10 deletions(-) diff --git a/fs/btrfs/messages.c b/fs/btrfs/messages.c index 310a05cf95ef..23fc11af498a 100644 --- a/fs/btrfs/messages.c +++ b/fs/btrfs/messages.c @@ -252,14 +252,6 @@ void __cold _btrfs_printk(const struct btrfs_fs_info *fs_info, const char *fmt, } #endif -#ifdef CONFIG_BTRFS_ASSERT -void __cold __noreturn btrfs_assertfail(const char *expr, const char *file, int line) -{ - pr_err("assertion failed: %s, in %s:%d\n", expr, file, line); - BUG(); -} -#endif - void __cold btrfs_print_v0_err(struct btrfs_fs_info *fs_info) { btrfs_err(fs_info, diff --git a/fs/btrfs/messages.h b/fs/btrfs/messages.h index 99143bbf78a5..deedc1a168e2 100644 --- a/fs/btrfs/messages.h +++ b/fs/btrfs/messages.h @@ -4,6 +4,8 @@ #define BTRFS_MESSAGES_H #include +#include +#include struct btrfs_fs_info; @@ -167,7 +169,11 @@ do { \ } while (0) #ifdef CONFIG_BTRFS_ASSERT -void __cold __noreturn btrfs_assertfail(const char *expr, const char *file, int line); + +#define btrfs_assertfail(expr, file, line) ({ \ + pr_err("assertion failed: %s, in %s:%d\n", (expr), (file), (line)); \ + BUG(); \ +}) #define ASSERT(expr) \ (likely(expr) ? (void)0 : btrfs_assertfail(#expr, __FILE__, __LINE__)) diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 0fcf99c91400..c19b1103e4ec 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -204,7 +204,6 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func, "__ubsan_handle_builtin_unreachable", "arch_call_rest_init", "arch_cpu_idle_dead", - "btrfs_assertfail", "cpu_bringup_and_idle", "cpu_startup_entry", "do_exit",