| Message ID | alpine.LSU.2.11.1401120043210.1092@eggly.anvils (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
On Sun, 2014-01-12 at 00:46 -0800, Hugh Dickins wrote: > My PowerMac G5 cannot boot mmotm these days: different symptoms > (starting /sbin/init failed? or ATA errors and hang?), with unrelated > bugs adding to the confusion; but a bisection led to b5ff4211a829 > "powerpc/book3s: Queue up and process delayed MCE events". Since that > series seems to be mostly about powernv, I tried changing BOOK3S_64 > to POWERNV in entry_64.S, which has got it back to working for me. > > Signed-off-by: Hugh Dickins <hughd@google.com> > just in case this happens to be right, but it's well beyond me! Mahesh, I think that code is broken. It calls into C code after R3 is loaded which will clobber it, thus clobbering the return from syscalls. Also, are you really adding that overhead to every syscall in the system ? That doesn't sound great... Why do you do something in syscall_exit to begin with anyway ? That doesn't seen like a great way to process delayed mchecks... When do you want to process them ? Any interruptible code ? Task level ? The former, you might be better off just shooting something like a local doorbell and use some IPI message bit or similar to indicate the presence of a pending mcheck. The local doorbell will trigger whenever interrupts are enabled. Ben. > --- > > arch/powerpc/kernel/entry_64.S | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > --- mmotm/arch/powerpc/kernel/entry_64.S 2014-01-10 18:24:56.940448828 -0800 > +++ linux/arch/powerpc/kernel/entry_64.S 2014-01-10 18:29:24.276455182 -0800 > @@ -184,7 +184,7 @@ syscall_exit: > bl .do_show_syscall_exit > ld r3,RESULT(r1) > #endif > -#ifdef CONFIG_PPC_BOOK3S_64 > +#ifdef CONFIG_PPC_POWERNV > BEGIN_FTR_SECTION > bl .machine_check_process_queued_event > END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
--- mmotm/arch/powerpc/kernel/entry_64.S 2014-01-10 18:24:56.940448828 -0800 +++ linux/arch/powerpc/kernel/entry_64.S 2014-01-10 18:29:24.276455182 -0800 @@ -184,7 +184,7 @@ syscall_exit: bl .do_show_syscall_exit ld r3,RESULT(r1) #endif -#ifdef CONFIG_PPC_BOOK3S_64 +#ifdef CONFIG_PPC_POWERNV BEGIN_FTR_SECTION bl .machine_check_process_queued_event END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
My PowerMac G5 cannot boot mmotm these days: different symptoms (starting /sbin/init failed? or ATA errors and hang?), with unrelated bugs adding to the confusion; but a bisection led to b5ff4211a829 "powerpc/book3s: Queue up and process delayed MCE events". Since that series seems to be mostly about powernv, I tried changing BOOK3S_64 to POWERNV in entry_64.S, which has got it back to working for me. Signed-off-by: Hugh Dickins <hughd@google.com> just in case this happens to be right, but it's well beyond me! --- arch/powerpc/kernel/entry_64.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)