On Tue, Oct 10, 2017 at 05:03:44PM +0100, Robin Murphy wrote: > On 10/10/17 16:45, Mark Rutland wrote: > > On Tue, Oct 10, 2017 at 10:27:25PM +0800, Leo Yan wrote: > >> Hi Mark, > > > > Hi Leo, > > > >> I work mainline kernel on Hikey620 board, I find it's easily to > >> introduce the panic and report the log as below. So I bisect the kernel > >> and finally narrow down the commit e3067861ba66 ("arm64: add basic > >> VMAP_STACK support") which introduce this issue. > >> > >> I tried to remove 'select HAVE_ARCH_VMAP_STACK' from > >> arch/arm64/Kconfig, then I can see the panic issue will dismiss. So > >> could you check this and have insight for this issue? > > > > Given the stuff in the backtrace, my suspicion is something is trying to > > perform DMA to/from the stack, getting junk addresses form the attempted > > virt<->phys conversions. > > > > Could you try enabling both VMAP_STACK and CONFIG_DEBUG_VIRTUAL? > > CONFIG_DMA_API_DEBUG should scream about drivers trying to use stack > addresses either way, too.
Thanks for suggestions, Mark & Robin. I enabled these debugging configs but cannot get clue from it; but occasionally found this issue is quite likely related with CA53 errata, especialy ERRATA_A53_855873 is the relative one. So I changed to use ARM-TF mainline code with ERRATA fixing, this issue can be dismissed. Please ignore this regression reporting. Thanks, Leo Yan