Bug 202963
| Summary: | [REGRESSION][BISECTED] Bluetooth broken on MBP and kernel NULL pointer dereference | ||
|---|---|---|---|
| Product: | Drivers | Reporter: | Ronald (ronald) |
| Component: | Bluetooth | Assignee: | linux-bluetooth (linux-bluetooth) |
| Status: | NEW --- | ||
| Severity: | high | CC: | btpython |
| Priority: | P1 | ||
| Hardware: | Intel | ||
| OS: | Linux | ||
| Kernel Version: | 5.0.2 | Subsystem: | |
| Regression: | Yes | Bisected commit-id: | |
| Attachments: | remove call regulator_bulk_enable() in bcm_gpio_set_power() | ||
Created attachment 281967 [details]
remove call regulator_bulk_enable() in bcm_gpio_set_power()
Btw., I tested https://lkml.org/lkml/2019/3/31/344 and that fixes the issue. Also, since this is a regression in 5.0, it would be nice to get this backported to 5.0 stable (and 5.1 in case it doesn't make it in there for release). (In reply to Ronald from comment #2) > Btw., I tested https://lkml.org/lkml/2019/3/31/344 and that fixes the issue. Forgot to add: more confirmations that this fixes the issue can be found at https://github.com/Dunedan/mbp-2016-linux/issues/97#issuecomment-482865366 |
Hardware: Apple MacBook Pro 13,3 As of kernel 5.0 bluetooth is not working anymore and there are a couple null pointer deference bugs in the dmesg during boot (this also delays boot and shutdown by several minutes). The issue has been bisected down to commit 75d11676dccb643de1e850c8a29f5e9aa58157c0 (Bluetooth: hci_bcm: Add support for regulator supplies). Further investigation shows the reason why: at the top of bcm_get_resources() processing is short-circuited on apple machines, and hence dev->supplies is never initialized; this then eventually leads to the null pointer after bcm_gpio_set_power() calls regulator_bulk_enable(). Two obvious fixes I see are: 1. don't call regulator_bulk_enable() if dev->supplies is not initialized 2. initialize dev->supplies on apple machines too For reference the BUG in dmesg is: BUG: unable to handle kernel NULL pointer dereference at 0000000000000088 #PF error: [normal kernel read fault] PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI CPU: 2 PID: 439 Comm: kworker/u16:2 Tainted: G W OE 5.0.2+ #4 Hardware name: Apple Inc. MacBookPro13,3/Mac-A5C67F76ED83108C, BIOS 251.0.0.0.0 10/> Workqueue: events_unbound async_run_entry_fn RIP: 0010:regulator_enable+0xe/0xc0 Code: ac ff 8b 43 0c e9 e2 fe ff ff e9 98 22 00 00 66 66 2e 0f 1f 84 00 00 00 00 00> RSP: 0018:ffffa8f1c25cfd98 EFLAGS: 00010282 RAX: ffffffffac63bef0 RBX: ffff926c1eda6ec8 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000001 R09: 00000000001e1f80 R10: 00000010213103a9 R11: ffffffffae650180 R12: ffff926c2d812000 R13: ffff926c2d859b00 R14: 0000000000000000 R15: ffff926c21a4a6e8 FS: 0000000000000000(0000) GS:ffff926c2e000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000088 CR3: 000000016b616004 CR4: 00000000003606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ? sched_clock+0x5/0x10 ? process_one_work+0x1ca/0x5f0 ? __lock_is_held+0x5a/0xa0 regulator_bulk_enable_async+0x12/0x20 async_run_entry_fn+0x39/0x160 process_one_work+0x24c/0x5f0 worker_thread+0x3c/0x390 ? process_one_work+0x5f0/0x5f0 kthread+0x120/0x140 ? kthread_create_on_node+0x60/0x60 ret_from_fork+0x3a/0x50 Modules linked in: acpi_cpufreq(E-) x86_pkg_temp_thermal(E) brcmfmac(E) intel_power> CR2: 0000000000000088 regulator_enable+0xe is this line (i.e. regulator is null): struct regulator_dev *rdev = regulator->rdev;