Messages in this thread | | | Date | Fri, 20 May 2022 08:08:59 +0800 (GMT+08:00) | From | duoming@zju ... | Subject | Re: [PATCH net v2] net: wireless: marvell: mwifiex: fix sleep in atomic context bugs |
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Hello,
On Thu, 19 May 2022 08:48:44 -0700 Jeff Johnson wrote:
> >>> There are sleep in atomic context bugs when uploading device dump > >>> data on usb interface. The root cause is that the operations that > >>> may sleep are called in fw_dump_timer_fn which is a timer handler. > >>> The call tree shows the execution paths that could lead to bugs: > >>> > >>> (Interrupt context) > >>> fw_dump_timer_fn > >>> mwifiex_upload_device_dump > >>> dev_coredumpv(..., GFP_KERNEL) > > just looking at this description, why isn't the simple fix just to > change this call to use GFP_ATOMIC?
Because change the parameter of dev_coredumpv() to GFP_ATOMIC could only solve partial problem. The following GFP_KERNEL parameters are in /lib/kobject.c which is not influenced by dev_coredumpv().
kobject_set_name_vargs kvasprintf_const(GFP_KERNEL, ...); //may sleep kstrdup(s, GFP_KERNEL); //may sleep
Best regards, Duoming Zhou | |