Re: crash by cdc_acm driver in kernels 4.8-rc1/5
From: Wim Osterholt
Date: Wed Sep 28 2016 - 10:47:05 EST
On Wed, Sep 28, 2016 at 11:16:04AM +0200, Oliver Neukum wrote:
> Very good. This is a valid oops. We can do two things. When I
> decode it, seems to crash in acm_alloc_minor() which does not make
> sense. It is likely that our kernels or compilers are a bit different.
> Could you please call gdb on your kernel module cdc-acm.ko
> and do:
> list *(acm_probe+0x4ee)
> this should show you where it crashes.
This is from vanilla kernel 4.8-rc8
# gdb ./cdc-acm.ko
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Reading symbols from ./cdc-acm.ko...done.
(gdb) list *(acm_probe+0x4ee)
0x1c9b is in acm_probe (drivers/usb/class/cdc-acm.c:1346).
1341 acm->control = control_interface;
1342 acm->data = data_interface;
1343 acm->minor = minor;
1344 acm->dev = usb_dev;
1345 if (h.usb_cdc_acm_descriptor)
1346 acm->ctrl_caps = h.usb_cdc_acm_descriptor->bmCapabilities;
1347 if (quirks & NO_CAP_LINE)
1348 acm->ctrl_caps &= ~USB_CDC_CAP_LINE;
1349 acm->ctrlsize = ctrlsize;
1350 acm->readsize = readsize;
A new kernel is compiling now.