On Tue, Nov 02, 2021 at 03:59:16AM +0000, 胡启航(Nick Hu) wrote:
> > -----Original Message-----
> > From: Peter Chen <peter.chen@xxxxxxxxxx>
> > Sent: Monday, November 1, 2021 9:19 PM
> > To: 胡启航(Nick Hu) <huqihang@xxxxxxxx>
> > Cc: balbi@xxxxxxxxxx; gregkh@xxxxxxxxxxxxxxxxxxx; linux-usb@xxxxxxxxxxxxxxx;
> > linux-kernel@xxxxxxxxxxxxxxx
> > Subject: Re: [PATCH] usb: gadget: composite: Fix null pointer exception
> >
> > On 21-11-01 09:57:57, Qihang Hu wrote:
> > > In the config_ep_by_speed_and_alt function, select the corresponding
> > > descriptor through g->speed, but the interface driver
> >
> > function driver
> >
> > > may not
> > > support the corresponding speed. So, we need to check whether the
> > > interface driver provides the corresponding speed descriptor when
> > > selecting the descriptor.
> > >
> > > [ 237.708146] android_work: sent uevent USB_STATE=CONNECTED
> > > [ 237.712464] kconfigfs-gadget gadget: super-speed config #1: b
> > > [ 237.712487] kUnable to handle kernel NULL pointer dereference at
> > virtual address 0000000000000000
> > > [ 237.712493] kMem abort info:
> > > [ 237.712498] k ESR = 0x96000006
> > > [ 237.712504] k EC = 0x25: DABT (current EL), IL = 32 bits
> > > [ 237.712510] k SET = 0, FnV = 0
> > > [ 237.712515] k EA = 0, S1PTW = 0
> > > [ 237.712520] kData abort info:
> > > [ 237.712525] k ISV = 0, ISS = 0x00000006
> > > [ 237.712530] k CM = 0, WnR = 0
> > > [ 237.712536] kuser pgtable: 4k pages, 39-bit VAs,
> > pgdp=000000020ef29000
> > > [ 237.712541] k[0000000000000000] pgd=000000020ef2a003,
> > pud=000000020ef2a003, pmd=0000000000000000
> > > [ 237.712554] kInternal error: Oops: 96000006 [#1] PREEMPT SMP
> > > [ 237.722067] kSkip md ftrace buffer dump for: 0x1609e0
> > > [ 237.787037] kWorkqueue: dwc_wq dwc3_bh_work.cfi_jt
> > > [ 237.854922] kpstate: 60c00085 (nZCv daIf +PAN +UAO)
> > > [ 237.863165] kpc : config_ep_by_speed_and_alt+0x90/0x308
> > > [ 237.871766] klr : audio_set_alt+0x54/0x78
> > > [ 237.879108] ksp : ffffffc0104839e0
> > >
> > > Signed-off-by: Qihang Hu <huqihang@xxxxxxxx>
> > > ---
> > > drivers/usb/gadget/composite.c | 6 +++---
> > > 1 file changed, 3 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
> > > index 72a9797dbbae..443a65af98af 100644
> > > --- a/drivers/usb/gadget/composite.c
> > > +++ b/drivers/usb/gadget/composite.c
> > > @@ -166,21 +166,21 @@ int config_ep_by_speed_and_alt(struct usb_gadget
> > *g,
> > > /* select desired speed */
> > > switch (g->speed) {
> > > case USB_SPEED_SUPER_PLUS:
> > > - if (gadget_is_superspeed_plus(g)) {
> > > + if (gadget_is_superspeed_plus(g) && f->ssp_descriptors) {
> > > speed_desc = f->ssp_descriptors;
> > > want_comp_desc = 1;
> > > break;
> > > }
> > > fallthrough;
> > > case USB_SPEED_SUPER:
> > > - if (gadget_is_superspeed(g)) {
> > > + if (gadget_is_superspeed(g) && f->ss_descriptors) {
> > > speed_desc = f->ss_descriptors;
> > > want_comp_desc = 1;
> > > break;
> > > }
> > > fallthrough;
> > > case USB_SPEED_HIGH:
> > > - if (gadget_is_dualspeed(g)) {
> > > + if (gadget_is_dualspeed(g) && f->hs_descriptors) {
> > > speed_desc = f->hs_descriptors;
> > > break;
> > > }
> > > --
> > > 2.25.1
> > >
> >
> > Besides your fix, you may show an warning that said "the function
> > doesn't hold the descriptors for supported speed, using the default (FS)
> > descriptors". See below kernel doc for detail.
> >
> > /**
> > * config_ep_by_speed_and_alt() - configures the given endpoint
> > *
> > * ....
> > * Note: the supplied function should hold all the descriptors
> > * for supported speeds
> > */
> >
> > What's more, you may fix android f_audio_source.c, and let it support
> > super speed and super speed plus.
> >
> > --
> >
> > Thanks,
> > Peter Chen
>
>
>
> From 9b8262792b6e85e6060601dbfc651b1e75b649f0 Mon Sep 17 00:00:00 2001
> From: Qihang Hu <huqihang@xxxxxxxx>
> Date: Sat, 30 Oct 2021 16:11:38 +0800
> Subject: [PATCH] usb: gadget: composite: Fix null pointer exception
>
> In the config_ep_by_speed_and_alt function, select the corresponding
> descriptor through g->speed, but the function driver may not
> support the corresponding speed. So, we need to check whether the
> function driver provides the corresponding speed descriptor when
> selecting the descriptor.
>
> [ 237.708146] android_work: sent uevent USB_STATE=CONNECTED
> [ 237.712464] kconfigfs-gadget gadget: super-speed config #1: b
> [ 237.712487] kUnable to handle kernel NULL pointer dereference at virtual address 0000000000000000
> [ 237.712493] kMem abort info:
> [ 237.712498] k ESR = 0x96000006
> [ 237.712504] k EC = 0x25: DABT (current EL), IL = 32 bits
> [ 237.712510] k SET = 0, FnV = 0
> [ 237.712515] k EA = 0, S1PTW = 0
> [ 237.712520] kData abort info:
> [ 237.712525] k ISV = 0, ISS = 0x00000006
> [ 237.712530] k CM = 0, WnR = 0
> [ 237.712536] kuser pgtable: 4k pages, 39-bit VAs, pgdp=000000020ef29000
> [ 237.712541] k[0000000000000000] pgd=000000020ef2a003, pud=000000020ef2a003, pmd=0000000000000000
> [ 237.712554] kInternal error: Oops: 96000006 [#1] PREEMPT SMP
> [ 237.722067] kSkip md ftrace buffer dump for: 0x1609e0
> [ 237.787037] kWorkqueue: dwc_wq dwc3_bh_work.cfi_jt
> [ 237.854922] kpstate: 60c00085 (nZCv daIf +PAN +UAO)
> [ 237.863165] kpc : config_ep_by_speed_and_alt+0x90/0x308
> [ 237.871766] klr : audio_set_alt+0x54/0x78
> [ 237.879108] ksp : ffffffc0104839e0
>
> Signed-off-by: Qihang Hu <huqihang@xxxxxxxx>
> ---
> drivers/usb/gadget/composite.c | 39 ++++++++++++++++++++++------------
> 1 file changed, 26 insertions(+), 13 deletions(-)
I can not take patches at the end of other email messages.
Please send this properly as a v2 patch, as the documentation asks for.
thanks,
greg k-h
