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Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git…
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…/paulus/powerpc

Pull powerpc fixes from Paul Mackerras:
 "Two small fixes for powerpc:
   - a fix for a regression since 3.2 that causes 4-second (or longer)
     pauses
   - a fix for a potential oops when loading kernel modules on 32-bit
     embedded systems."

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
  powerpc: Fix kernel panic during kernel module load
  powerpc/time: Sanity check of decrementer expiration is necessary
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torvalds committed Jun 8, 2012
2 parents e726430 + 3c75296 commit 3e9ca02
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Showing 2 changed files with 16 additions and 9 deletions.
11 changes: 5 additions & 6 deletions arch/powerpc/kernel/module_32.c
Original file line number Diff line number Diff line change
Expand Up @@ -176,8 +176,8 @@ int module_frob_arch_sections(Elf32_Ehdr *hdr,

static inline int entry_matches(struct ppc_plt_entry *entry, Elf32_Addr val)
{
if (entry->jump[0] == 0x3d600000 + ((val + 0x8000) >> 16)
&& entry->jump[1] == 0x396b0000 + (val & 0xffff))
if (entry->jump[0] == 0x3d800000 + ((val + 0x8000) >> 16)
&& entry->jump[1] == 0x398c0000 + (val & 0xffff))
return 1;
return 0;
}
Expand All @@ -204,10 +204,9 @@ static uint32_t do_plt_call(void *location,
entry++;
}

/* Stolen from Paul Mackerras as well... */
entry->jump[0] = 0x3d600000+((val+0x8000)>>16); /* lis r11,sym@ha */
entry->jump[1] = 0x396b0000 + (val&0xffff); /* addi r11,r11,sym@l*/
entry->jump[2] = 0x7d6903a6; /* mtctr r11 */
entry->jump[0] = 0x3d800000+((val+0x8000)>>16); /* lis r12,sym@ha */
entry->jump[1] = 0x398c0000 + (val&0xffff); /* addi r12,r12,sym@l*/
entry->jump[2] = 0x7d8903a6; /* mtctr r12 */
entry->jump[3] = 0x4e800420; /* bctr */

DEBUGP("Initialized plt for 0x%x at %p\n", val, entry);
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14 changes: 11 additions & 3 deletions arch/powerpc/kernel/time.c
Original file line number Diff line number Diff line change
Expand Up @@ -475,6 +475,7 @@ void timer_interrupt(struct pt_regs * regs)
struct pt_regs *old_regs;
u64 *next_tb = &__get_cpu_var(decrementers_next_tb);
struct clock_event_device *evt = &__get_cpu_var(decrementers);
u64 now;

/* Ensure a positive value is written to the decrementer, or else
* some CPUs will continue to take decrementer exceptions.
Expand Down Expand Up @@ -509,9 +510,16 @@ void timer_interrupt(struct pt_regs * regs)
irq_work_run();
}

*next_tb = ~(u64)0;
if (evt->event_handler)
evt->event_handler(evt);
now = get_tb_or_rtc();
if (now >= *next_tb) {
*next_tb = ~(u64)0;
if (evt->event_handler)
evt->event_handler(evt);
} else {
now = *next_tb - now;
if (now <= DECREMENTER_MAX)
set_dec((int)now);
}

#ifdef CONFIG_PPC64
/* collect purr register values often, for accurate calculations */
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