diff options
author | John Garry <john.garry@huawei.com> | 2019-07-30 21:29:56 +0800 |
---|---|---|
committer | Wei Xu <xuwei5@hisilicon.com> | 2019-08-13 14:54:34 +0800 |
commit | 10e62b47973b0b0ceda076255bcb147b83e20517 (patch) | |
tree | 3feb8be4883720cfbc1853e9c98a8696abdbca24 /drivers | |
parent | 1b15a5632a809ab57d403fd972ca68785363b654 (diff) |
bus: hisi_lpc: Add .remove method to avoid driver unbind crash
The original driver author seemed to be under the impression that a driver
cannot be removed if it does not have a .remove method. Or maybe if it is
a built-in platform driver.
This is not true. This crash can be created:
root@ubuntu:/sys/bus/platform/drivers/hisi-lpc# echo HISI0191\:00 > unbind
root@ubuntu:/sys/bus/platform/drivers/hisi-lpc# ipmitool raw 6 1
Unable to handle kernel paging request at virtual address ffff000010035010
Mem abort info:
ESR = 0x96000047
Exception class = DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
Data abort info:
ISV = 0, ISS = 0x00000047
CM = 0, WnR = 1
swapper pgtable: 4k pages, 48-bit VAs, pgdp=000000000118b000
[ffff000010035010] pgd=0000041ffbfff003, pud=0000041ffbffe003, pmd=0000041ffbffd003, pte=0000000000000000
Internal error: Oops: 96000047 [#1] PREEMPT SMP
Modules linked in:
CPU: 17 PID: 1473 Comm: ipmitool Not tainted 5.2.0-rc5-00003-gf68c53b414a3-dirty #198
Hardware name: Huawei Taishan 2280 /D05, BIOS Hisilicon D05 IT21 Nemo 2.0 RC0 04/18/2018
pstate: 20000085 (nzCv daIf -PAN -UAO)
pc : hisi_lpc_target_in+0x7c/0x120
lr : hisi_lpc_target_in+0x70/0x120
sp : ffff00001efe3930
x29: ffff00001efe3930 x28: ffff841f9f599200
x27: 0000000000000002 x26: 0000000000000000
x25: 0000000000000080 x24: 00000000000000e4
x23: 0000000000000000 x22: 0000000000000064
x21: ffff801fb667d280 x20: 0000000000000001
x19: ffff00001efe39ac x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000
x15: 0000000000000000 x14: 0000000000000000
x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000000000 x10: 0000000000000000
x9 : 0000000000000000 x8 : ffff841febe60340
x7 : ffff801fb55c52e8 x6 : 0000000000000000
x5 : 0000000000ffc0e3 x4 : 0000000000000001
x3 : ffff801fb667d280 x2 : 0000000000000001
x1 : ffff000010035010 x0 : ffff000010035000
Call trace:
hisi_lpc_target_in+0x7c/0x120
hisi_lpc_comm_in+0x88/0x98
logic_inb+0x5c/0xb8
port_inb+0x18/0x20
bt_event+0x38/0x808
smi_event_handler+0x4c/0x5a0
check_start_timer_thread.part.4+0x40/0x58
sender+0x78/0x88
smi_send.isra.6+0x94/0x108
i_ipmi_request+0x2c4/0x8f8
ipmi_request_settime+0x124/0x160
handle_send_req+0x19c/0x208
ipmi_ioctl+0x2c0/0x990
do_vfs_ioctl+0xb8/0x8f8
ksys_ioctl+0x80/0xb8
__arm64_sys_ioctl+0x1c/0x28
el0_svc_common.constprop.0+0x64/0x160
el0_svc_handler+0x28/0x78
el0_svc+0x8/0xc
Code: 941d1511 aa0003f9 f94006a0 91004001 (b9000034)
---[ end trace aa842b86af7069e4 ]---
The problem here is that the host goes away but the associated logical PIO
region remains registered, as do the children devices.
Fix by adding a .remove method to tidy-up by removing the child devices
and unregistering the logical PIO region.
Cc: stable@vger.kernel.org
Fixes: adf38bb0b595 ("HISI LPC: Support the LPC host on Hip06/Hip07 with DT bindings")
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/bus/hisi_lpc.c | 38 |
1 files changed, 36 insertions, 2 deletions
diff --git a/drivers/bus/hisi_lpc.c b/drivers/bus/hisi_lpc.c index 6d301aafcad2..20c957185af2 100644 --- a/drivers/bus/hisi_lpc.c +++ b/drivers/bus/hisi_lpc.c @@ -456,6 +456,17 @@ struct hisi_lpc_acpi_cell { size_t pdata_size; }; +static void hisi_lpc_acpi_remove(struct device *hostdev) +{ + struct acpi_device *adev = ACPI_COMPANION(hostdev); + struct acpi_device *child; + + device_for_each_child(hostdev, NULL, hisi_lpc_acpi_remove_subdev); + + list_for_each_entry(child, &adev->children, node) + acpi_device_clear_enumerated(child); +} + /* * hisi_lpc_acpi_probe - probe children for ACPI FW * @hostdev: LPC host device pointer @@ -555,8 +566,7 @@ static int hisi_lpc_acpi_probe(struct device *hostdev) return 0; fail: - device_for_each_child(hostdev, NULL, - hisi_lpc_acpi_remove_subdev); + hisi_lpc_acpi_remove(hostdev); return ret; } @@ -569,6 +579,10 @@ static int hisi_lpc_acpi_probe(struct device *dev) { return -ENODEV; } + +static void hisi_lpc_acpi_remove(struct device *hostdev) +{ +} #endif // CONFIG_ACPI /* @@ -626,6 +640,8 @@ static int hisi_lpc_probe(struct platform_device *pdev) return ret; } + dev_set_drvdata(dev, lpcdev); + io_end = lpcdev->io_host->io_start + lpcdev->io_host->size; dev_info(dev, "registered range [%pa - %pa]\n", &lpcdev->io_host->io_start, &io_end); @@ -633,6 +649,23 @@ static int hisi_lpc_probe(struct platform_device *pdev) return ret; } +static int hisi_lpc_remove(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct acpi_device *acpi_device = ACPI_COMPANION(dev); + struct hisi_lpc_dev *lpcdev = dev_get_drvdata(dev); + struct logic_pio_hwaddr *range = lpcdev->io_host; + + if (acpi_device) + hisi_lpc_acpi_remove(dev); + else + of_platform_depopulate(dev); + + logic_pio_unregister_range(range); + + return 0; +} + static const struct of_device_id hisi_lpc_of_match[] = { { .compatible = "hisilicon,hip06-lpc", }, { .compatible = "hisilicon,hip07-lpc", }, @@ -646,5 +679,6 @@ static struct platform_driver hisi_lpc_driver = { .acpi_match_table = ACPI_PTR(hisi_lpc_acpi_match), }, .probe = hisi_lpc_probe, + .remove = hisi_lpc_remove, }; builtin_platform_driver(hisi_lpc_driver); |