Re: arm64 dragonboard 410c Internal error Oops dev_pm_opp_put core_clks_enable

[Renjiang Han]

On 7/18/2025 7:28 PM, Arnd Bergmann wrote:
> On Fri, Jul 18, 2025, at 13:13, Naresh Kamboju wrote:
> > The following Boot regressions are noticed on the Linux
> > next-20250708with gcc-13 and clang-20 toolchains for the dragonboard
> > 410c device.
> > [   12.629924] x5 : 0000000000000002 x4 : 00000000c0000000 x3 :
> > 0000000000000001
> > [   12.629939] x2 : 0000000000000002 x1 : ffffffffffffffde x0 :
> > ffffffffffffffee
> > [   12.629956] Call trace:
> > [   12.629962]  dev_pm_opp_put+0x24/0x58 (P)
> > [   12.629981]  core_clks_enable+0x54/0x148 venus_core
> > [   12.630064]  core_power_v1+0x78/0x90 venus_core
> > [   12.691130]  venus_runtime_resume+0x6c/0x98 venus_core
> > [   12.817608] Code: 910003fd f9000bf3 91004013 aa1303e0 (f9402821)
> > All code
> > ========
> >     0: 910003fd mov x29, sp
> >     4: f9000bf3 str x19, [sp, #16]
> >     8: 91004013 add x19, x0, #0x10
> >     c: aa1303e0 mov x0, x19
> >    10:* f9402821 ldr x1, [x1, #80] <-- trapping instruction
> It's loading from 'x1', which is an error pointer ffffffffffffffde
> (-EISCONN).  The caller was modified by Renjiang Han (added to Cc)
> in commit b179234b5e59 ("media: venus: pm_helpers: use opp-table
> for the frequency").
>
> The new version of the code is now
>
> static int core_clks_enable(struct venus_core *core)
>   {
>          const struct venus_resources *res = core->res;
> +       struct device *dev = core->dev;
> +       unsigned long freq = 0;
> +       struct dev_pm_opp *opp;
>          unsigned int i;
>          int ret;
>   
> +       opp = dev_pm_opp_find_freq_ceil(dev, &freq);
> +       dev_pm_opp_put(opp);
>   
> Where the 'opp' pointer is the error code and gets passed
> into dev_pm_opp_put() without checking for the error condition.
Thank you for pointing it out.
I have submitted the following patch to fix this issue.
https://lore.kernel.org/linux-arm-msm/20250723-fallback_of_opp_table-v1-1-20a6277fdded@xxxxxxxxxxx
>      Arnd

--
Best Regards,
Renjiang