Upon module load, mmc_block allocates a bus with bus_register in mmc_blk_init. This reference never gets freed during module unload. Subsequent re-insertions of the module fail and BUG() is triggered: [ 84.583342] sysfs: cannot create duplicate filename '/bus/mmc_rpmb' [ 84.583373] CPU: 6 PID: 1825 Comm: modprobe Tainted: P O 4.16.0-rc6-00384-gf36b753 #30 [ 84.583381] Hardware name: LENOVO 20ENCTO1WW/20ENCTO1WW, BIOS N1EET62W (1.35 ) 11/10/2016 [ 84.583385] Call Trace: [ 84.583401] dump_stack+0x5a/0x75 [ 84.583411] sysfs_warn_dup+0x58/0x70 [ 84.583419] sysfs_create_dir_ns+0x70/0x80 [ 84.583437] kobject_add_internal+0xa5/0x2c0 [ 84.583453] kset_register+0x44/0x60 [ 84.583470] bus_register+0xc6/0x270 [ 84.583479] ? 0xffffffffa000d000 [ 84.583492] mmc_blk_init+0x12/0x1000 [mmc_block] [ 84.583501] do_one_initcall+0x4e/0x194 [ 84.583510] ? ___cache_free+0x21/0x2b0 [ 84.583524] do_init_module+0x5a/0x20f [ 84.583533] load_module+0x235c/0x2510 [ 84.583550] ? SYSC_finit_module+0x80/0xb0 [ 84.583558] SYSC_finit_module+0x80/0xb0 [ 84.583570] do_syscall_64+0x77/0x290 [ 84.583580] entry_SYSCALL_64_after_hwframe+0x3d/0xa2 [ 84.583587] RIP: 0033:0x7f452a3ad5b9 [ 84.583593] RSP: 002b:00007fff4562ba18 EFLAGS: 00000206 ORIG_RAX: 0000000000000139 [ 84.583602] RAX: ffffffffffffffda RBX: 000056092895c520 RCX: 00007f452a3ad5b9 [ 84.583607] RDX: 0000000000000000 RSI: 000056092697b3d9 RDI: 0000000000000003 [ 84.583612] RBP: 000056092697b3d9 R08: 0000000000000000 R09: 000056092895d310 [ 84.583617] R10: 0000000000000003 R11: 0000000000000206 R12: 0000000000000000 [ 84.583623] R13: 000056092895c430 R14: 0000000000040000 R15: 0000000000040000 [ 84.583647] ------------[ cut here ]------------ [ 84.583656] kobject_add_internal failed for mmc_rpmb with -EEXIST, don't try to register things with the same name in the same directory. [ 84.583694] WARNING: CPU: 6 PID: 1825 at lib/kobject.c:238 kobject_add_internal+0x296/0x2c0 [ 84.583705] Modules linked in: mmc_block(+) rtsx_pci_sdmmc rtsx_pci iwlmvm mac80211 nvidia_drm(PO) nvidia_modeset(PO) iwlwifi nvidia(PO) cfg80211 qmi_wwan thinkpad_acpi rfkill sdhci_pci cqhci sdhci mfd_core [last unloaded: mmc_block] [ 84.583770] CPU: 6 PID: 1825 Comm: modprobe Tainted: P O 4.16.0-rc6-00384-gf36b753 #30 [ 84.583774] Hardware name: LENOVO 20ENCTO1WW/20ENCTO1WW, BIOS N1EET62W (1.35 ) 11/10/2016 [ 84.583782] RIP: 0010:kobject_add_internal+0x296/0x2c0 [ 84.583786] RSP: 0018:ffffc9000769bc58 EFLAGS: 00010296 [ 84.583791] RAX: 000000000000007d RBX: ffff880fcf588618 RCX: 0000000000000000 [ 84.583796] RDX: 0000000000040400 RSI: 00000000000000f6 RDI: 00000000ffffffff [ 84.583801] RBP: 00000000ffffffef R08: 0000000000000000 R09: 0000000000000354 [ 84.583806] R10: ffffffff8251fc74 R11: 0000000000000353 R12: ffff88100d3cf698 [ 84.583811] R13: ffff880fcf588618 R14: ffffffffa0028590 R15: ffffffffa0028540 [ 84.583818] FS: 00007f452a853700(0000) GS:ffff881053d80000(0000) knlGS:0000000000000000 [ 84.583823] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 84.583837] CR2: 00007f452a3faea0 CR3: 0000000fc89e4004 CR4: 00000000003606e0 [ 84.583850] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 84.583863] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 84.583875] Call Trace: [ 84.583893] kset_register+0x44/0x60 [ 84.583902] bus_register+0xc6/0x270 [ 84.583910] ? 0xffffffffa000d000 [ 84.583926] mmc_blk_init+0x12/0x1000 [mmc_block] [ 84.583940] do_one_initcall+0x4e/0x194 [ 84.583948] ? ___cache_free+0x21/0x2b0 [ 84.583966] do_init_module+0x5a/0x20f [ 84.583979] load_module+0x235c/0x2510 [ 84.583995] ? SYSC_finit_module+0x80/0xb0 [ 84.584001] SYSC_finit_module+0x80/0xb0 [ 84.584010] do_syscall_64+0x77/0x290 [ 84.584016] entry_SYSCALL_64_after_hwframe+0x3d/0xa2 [ 84.584021] RIP: 0033:0x7f452a3ad5b9 [ 84.584025] RSP: 002b:00007fff4562ba18 EFLAGS: 00000206 ORIG_RAX: 0000000000000139 [ 84.584030] RAX: ffffffffffffffda RBX: 000056092895c520 RCX: 00007f452a3ad5b9 [ 84.584034] RDX: 0000000000000000 RSI: 000056092697b3d9 RDI: 0000000000000003 [ 84.584038] RBP: 000056092697b3d9 R08: 0000000000000000 R09: 000056092895d310 [ 84.584043] R10: 0000000000000003 R11: 0000000000000206 R12: 0000000000000000 [ 84.584047] R13: 000056092895c430 R14: 0000000000040000 R15: 0000000000040000 [ 84.584053] Code: 7b 20 49 89 c4 48 85 ff 0f 84 10 fe ff ff e9 cd fd ff ff 48 8b 13 48 c7 c6 00 80 f4 81 48 c7 c7 e0 ad 0f 82 31 c0 e8 ca 9a 7b ff <0f> 0b e9 5f fe ff ff 0f 0b 0f 0b 0f 0b 0f 0b e9 71 ff ff ff 0f [ 84.584147] ---[ end trace d27b36e0e2c0e7e5 ]--- [ 84.584162] mmcblk: could not register RPMB bus type Steps to reproduce: Build with CONFIG_MMC_BLOCK=m modprobe mmc_block rmmod mmc_block modprobe mmc_block The proposed patch deallocates the reference in mmc_blk_exit. Signed-off-by: Alexander Kappner <agk@xxxxxxxxxxx> --- drivers/mmc/core/block.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c index 2cfb963..9c6f639 100644 --- a/drivers/mmc/core/block.c +++ b/drivers/mmc/core/block.c @@ -3087,6 +3087,7 @@ static void __exit mmc_blk_exit(void) mmc_unregister_driver(&mmc_driver); unregister_blkdev(MMC_BLOCK_MAJOR, "mmc"); unregister_chrdev_region(mmc_rpmb_devt, MAX_DEVICES); + bus_unregister(&mmc_rpmb_bus_type); } module_init(mmc_blk_init); -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
