Hi Greg,
On Fri, Jul 10, 2015 at 10:28 AM, Kevin Hilman <khilman@xxxxxxxxxx> wrote:
> From: Tony Lindgren <tony@xxxxxxxxxxx>
>
> We get a NULL pointer dereference on omap3 for thumb2 compiled kernels:
>
> Internal error: Oops: 80000005 [#1] SMP THUMB2
> ...
> [<c046497b>] (_raw_spin_unlock_irqrestore) from [<c0024375>]
> (omap3_enter_idle_bm+0xc5/0x178)
> [<c0024375>] (omap3_enter_idle_bm) from [<c0374e63>]
> (cpuidle_enter_state+0x77/0x27c)
> [<c0374e63>] (cpuidle_enter_state) from [<c00627f1>]
> (cpu_startup_entry+0x155/0x23c)
> [<c00627f1>] (cpu_startup_entry) from [<c06b9a47>]
> (start_kernel+0x32f/0x338)
> [<c06b9a47>] (start_kernel) from [<8000807f>] (0x8000807f)
>
> The power management related assembly on omaps needs to interact with
> ARM mode bootrom code, so we need to keep most of the related assembly
> in ARM mode.
>
> Turns out this error is because of missing ENDPROC for assembly code
> as suggested by Stephen Boyd <sboyd@xxxxxxxxxxxxxx>. Let's fix the
> problem by adding ENDPROC in two places to sleep34xx.S.
>
> Let's also remove the now duplicate custom code for mode switching.
> This has been unnecessary since commit 6ebbf2ce437b ("ARM: convert
> all "mov.* pc, reg" to "bx reg" for ARMv6+").
>
> And let's also remove the comments about local variables, they are
> now just confusing after the ENDPROC.
>
> The reason why ENDPROC makes a difference is it sets .type and then
> the compiler knows what to do with the thumb bit as explained at:
>
> https://wiki.ubuntu.com/ARM/Thumb2PortingHowto
>
> Reported-by: Kevin Hilman <khilman@xxxxxxxxxx>
> Tested-by: Kevin Hilman <khilman@xxxxxxxxxx>
> Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx>
> (cherry picked from commit d8a50941c91a68da202aaa96a3dacd471ea9c693)
> Cc: <stable@xxxxxxxxxxxxxxx> # v4.0+
> Signed-off-by: Kevin Hilman <khilman@xxxxxxxxxx>
This one seems to be missing in v4.0.9, though it was submitted ~10
days before. I missed noticing it was not present in the stable queue
because I've been on vacation.
I know you mentioned you were wrapping up v4.0, but any chance of this
being included?
Thanks,
Kevin
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