From: James Hogan james.hogan@imgtec.com
commit 826e99be6ab5189dbfb096389016ffb8d20a683e upstream.
When a CPU is disabled via CPU hotplug, cpu_foreign_map is not updated. This could result in cache management SMP calls being sent to offline CPUs instead of online siblings in the same core.
Add a call to calculate_cpu_foreign_map() in the various MIPS cpu disable callbacks after set_cpu_online(). All cases are updated for consistency and to keep cpu_foreign_map strictly up to date, not just those which may support hardware multithreading.
Fixes: cccf34e9411c ("MIPS: c-r4k: Fix cache flushing for MT cores") Signed-off-by: James Hogan james.hogan@imgtec.com Cc: Paul Burton paul.burton@imgtec.com Cc: David Daney david.daney@cavium.com Cc: Kevin Cernekee cernekee@gmail.com Cc: Florian Fainelli f.fainelli@gmail.com Cc: Huacai Chen chenhc@lemote.com Cc: Hongliang Tao taohl@lemote.com Cc: Hua Yan yanh@lemote.com Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/13799/ Signed-off-by: Ralf Baechle ralf@linux-mips.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/mips/cavium-octeon/smp.c | 1 + arch/mips/include/asm/smp.h | 2 ++ arch/mips/kernel/smp-bmips.c | 1 + arch/mips/kernel/smp-cps.c | 1 + arch/mips/kernel/smp.c | 2 +- arch/mips/loongson64/loongson-3/smp.c | 1 + 6 files changed, 7 insertions(+), 1 deletion(-)
--- a/arch/mips/cavium-octeon/smp.c +++ b/arch/mips/cavium-octeon/smp.c @@ -239,6 +239,7 @@ static int octeon_cpu_disable(void) return -ENOTSUPP;
set_cpu_online(cpu, false); + calculate_cpu_foreign_map(); cpumask_clear_cpu(cpu, &cpu_callin_map); octeon_fixup_irqs();
--- a/arch/mips/include/asm/smp.h +++ b/arch/mips/include/asm/smp.h @@ -63,6 +63,8 @@ extern cpumask_t cpu_coherent_mask;
extern void asmlinkage smp_bootstrap(void);
+extern void calculate_cpu_foreign_map(void); + /* * this function sends a 'reschedule' IPI to another CPU. * it goes straight through and wastes no time serializing --- a/arch/mips/kernel/smp-bmips.c +++ b/arch/mips/kernel/smp-bmips.c @@ -362,6 +362,7 @@ static int bmips_cpu_disable(void) pr_info("SMP: CPU%d is offline\n", cpu);
set_cpu_online(cpu, false); + calculate_cpu_foreign_map(); cpumask_clear_cpu(cpu, &cpu_callin_map); clear_c0_status(IE_IRQ5);
--- a/arch/mips/kernel/smp-cps.c +++ b/arch/mips/kernel/smp-cps.c @@ -338,6 +338,7 @@ static int cps_cpu_disable(void) atomic_sub(1 << cpu_vpe_id(¤t_cpu_data), &core_cfg->vpe_mask); smp_mb__after_atomic(); set_cpu_online(cpu, false); + calculate_cpu_foreign_map(); cpumask_clear_cpu(cpu, &cpu_callin_map);
return 0; --- a/arch/mips/kernel/smp.c +++ b/arch/mips/kernel/smp.c @@ -118,7 +118,7 @@ static inline void set_cpu_core_map(int * Calculate a new cpu_foreign_map mask whenever a * new cpu appears or disappears. */ -static inline void calculate_cpu_foreign_map(void) +void calculate_cpu_foreign_map(void) { int i, k, core_present; cpumask_t temp_foreign_map; --- a/arch/mips/loongson64/loongson-3/smp.c +++ b/arch/mips/loongson64/loongson-3/smp.c @@ -417,6 +417,7 @@ static int loongson3_cpu_disable(void) return -EBUSY;
set_cpu_online(cpu, false); + calculate_cpu_foreign_map(); cpumask_clear_cpu(cpu, &cpu_callin_map); local_irq_save(flags); fixup_irqs();