Messages in this thread | | | Date | Sat, 20 Jun 2020 20:10:52 +0100 | From | Ivan Kokshaysky <> | Subject | Re: [PATCH] cpufreq: dt: fix oops on armada37xx |
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On Sat, Jun 20, 2020 at 07:54:38PM +0200, Andrew Lunn wrote: > On Sat, Jun 20, 2020 at 05:44:49PM +0100, Ivan Kokshaysky wrote: > > Commit 0c868627e617e43a295d8 (cpufreq: dt: Allow platform specific > > intermediate callbacks) added two function pointers to the > > struct cpufreq_dt_platform_data. However, armada37xx_cpufreq_driver_init() > > has this struct (pdata) located on the stack and uses only "suspend" > > and "resume" fields. So these newly added "get_intermediate" and > > "target_intermediate" pointers are uninitialized and contain arbitrary > > non-null values, causing all kinds of trouble. > > > > For instance, here is an oops on espressobin after an attempt to change > > the cpefreq governor: > > > > [ 29.174554] Unable to handle kernel execute from non-executable memory at virtual address ffff00003f87bdc0 > > ... > > [ 29.269373] pc : 0xffff00003f87bdc0 > > [ 29.272957] lr : __cpufreq_driver_target+0x138/0x580 > > ... > > > > Fixed by zeroing out pdata before use. > > > > Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru> > > Hi Ivan > > A Fixes: tag would be good.
Hi Andrew,
I'm not sure that "Fixes:" would be appropriate here - commit 0c868627e617 is fine by itself, it just revealed a bug in older code.
Thanks for reviewing, Ivan.
> Reviewed-by: Andrew Lunn <andrew@lunn.ch> > > Andrew
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