USB: serial: ftdi_sio: Add MTP NVM support
Quoted 10 lines · Loic Poulain
Hi Johan, Srini,
Quoted 6 lines · Srinivas Kandagatla
Quoted 4 lines · Johan Hovold
I'm not necessarily against the idea, but nvmem core needs to be fixed so that it can handle hotplugging before this can be considered for merging.
Quoted 8 lines
Quoted 4 lines
Quoted 4 lines
Right now it just returns
-EBUSYfromnvmem_unregister(), which results in all kinds of memory leaks, use-after-frees and crashes when user space holds the character device open while the device is being unplugged.Correct me if I'm wrong, but nvmem is just exposed to userspace as a simple sysfs device attribute (nvmem), removing a device and its attribute(s) dynamically is well managed by sysfs, even if userspace has file open.
My bad, I misremembered what interface nvmem was using and only saw the deregistration refusal in nvmem_unregister() during a quick check.
Quoted 2 lines
The only risk here is when a kernel internal consumer still has a reference to the nvmem device on removal, which is not the case in our context.
Right.
Quoted 3 lines
Quoted 1 line
I can also suggest you to try
devm_nvmem_register().Yes, I'm going to send a v2.
I'll take a closer look soonish too.
Johan
---
To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html