Re: [PATCH] powerpc/prom_init: Check display props exist before enabling btext

2020-09-24 Thread Michael Ellerman
On Fri, 21 Aug 2020 20:34:07 +1000, Michael Ellerman wrote: > It's possible to enable CONFIG_PPC_EARLY_DEBUG_BOOTX for a pseries > kernel (maybe it shouldn't be), which is then booted with qemu/slof. > > But if you do that the kernel crashes in draw_byte(), with a DAR > pointing somewhere near

Re: [PATCH] powerpc/prom_init: Check display props exist before enabling btext

2020-08-23 Thread Michael Ellerman
Alexey Kardashevskiy writes: > On 21/08/2020 20:34, Michael Ellerman wrote: >> It's possible to enable CONFIG_PPC_EARLY_DEBUG_BOOTX for a pseries >> kernel (maybe it shouldn't be), which is then booted with qemu/slof. > > > CONFIG_BOOTX_TEXT=y > CONFIG_PPC_EARLY_DEBUG=y >

Re: [PATCH] powerpc/prom_init: Check display props exist before enabling btext

2020-08-22 Thread Alexey Kardashevskiy
On 21/08/2020 20:34, Michael Ellerman wrote: > It's possible to enable CONFIG_PPC_EARLY_DEBUG_BOOTX for a pseries > kernel (maybe it shouldn't be), which is then booted with qemu/slof. CONFIG_BOOTX_TEXT=y CONFIG_PPC_EARLY_DEBUG=y CONFIG_PPC_EARLY_DEBUG_BOOTX=y this does not crash my VM. The

[PATCH] powerpc/prom_init: Check display props exist before enabling btext

2020-08-21 Thread Michael Ellerman
It's possible to enable CONFIG_PPC_EARLY_DEBUG_BOOTX for a pseries kernel (maybe it shouldn't be), which is then booted with qemu/slof. But if you do that the kernel crashes in draw_byte(), with a DAR pointing somewhere near INT_MAX. Adding some debug to prom_init we see that we're not able to