diff options
| author | Mahesh Salgaonkar <mahesh@linux.ibm.com> | 2020-06-23 15:57:50 +0530 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2020-07-29 23:47:53 +1000 |
| commit | ada68a66b72687e6b74e35c42efd1783e84b01fd (patch) | |
| tree | b7e60ccb64c4a803d3049f7773651bcc7f2d10cd /arch/powerpc/kernel | |
| parent | d3c61954fc1827df571e235b9a98e10108ef5c3d (diff) | |
powerpc/64s: Move HMI IRQ stat from percpu variable to paca.
With the proposed change in percpu bootmem allocator to use page
mapping [1], the percpu first chunk memory area can come from vmalloc
ranges. This makes the HMI (Hypervisor Maintenance Interrupt) handler
crash the kernel whenever percpu variable is accessed in real mode.
This patch fixes this issue by moving the HMI IRQ stat inside paca for
safe access in realmode.
[1] https://lore.kernel.org/linuxppc-dev/20200608070904.387440-1-aneesh.kumar@linux.ibm.com/
Suggested-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/159290806973.3642154.5244613424529764050.stgit@jupiter
Diffstat (limited to 'arch/powerpc/kernel')
| -rw-r--r-- | arch/powerpc/kernel/irq.c | 9 | ||||
| -rw-r--r-- | arch/powerpc/kernel/mce.c | 2 |
2 files changed, 7 insertions, 4 deletions
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c index 05b1cc0e009e..bf21ebd36190 100644 --- a/arch/powerpc/kernel/irq.c +++ b/arch/powerpc/kernel/irq.c @@ -621,13 +621,14 @@ int arch_show_interrupts(struct seq_file *p, int prec) seq_printf(p, "%10u ", per_cpu(irq_stat, j).mce_exceptions); seq_printf(p, " Machine check exceptions\n"); +#ifdef CONFIG_PPC_BOOK3S_64 if (cpu_has_feature(CPU_FTR_HVMODE)) { seq_printf(p, "%*s: ", prec, "HMI"); for_each_online_cpu(j) - seq_printf(p, "%10u ", - per_cpu(irq_stat, j).hmi_exceptions); + seq_printf(p, "%10u ", paca_ptrs[j]->hmi_irqs); seq_printf(p, " Hypervisor Maintenance Interrupts\n"); } +#endif seq_printf(p, "%*s: ", prec, "NMI"); for_each_online_cpu(j) @@ -665,7 +666,9 @@ u64 arch_irq_stat_cpu(unsigned int cpu) sum += per_cpu(irq_stat, cpu).mce_exceptions; sum += per_cpu(irq_stat, cpu).spurious_irqs; sum += per_cpu(irq_stat, cpu).timer_irqs_others; - sum += per_cpu(irq_stat, cpu).hmi_exceptions; +#ifdef CONFIG_PPC_BOOK3S_64 + sum += paca_ptrs[cpu]->hmi_irqs; +#endif sum += per_cpu(irq_stat, cpu).sreset_irqs; #ifdef CONFIG_PPC_WATCHDOG sum += per_cpu(irq_stat, cpu).soft_nmi_irqs; diff --git a/arch/powerpc/kernel/mce.c b/arch/powerpc/kernel/mce.c index c2fa8ee63720..ada59f6c4298 100644 --- a/arch/powerpc/kernel/mce.c +++ b/arch/powerpc/kernel/mce.c @@ -727,7 +727,7 @@ long hmi_exception_realmode(struct pt_regs *regs) { int ret; - __this_cpu_inc(irq_stat.hmi_exceptions); + local_paca->hmi_irqs++; ret = hmi_handle_debugtrig(regs); if (ret >= 0) |