diff options
Diffstat (limited to 'arch/powerpc/mm/slb.c')
| -rw-r--r-- | arch/powerpc/mm/slb.c | 37 |
1 files changed, 33 insertions, 4 deletions
diff --git a/arch/powerpc/mm/slb.c b/arch/powerpc/mm/slb.c index de0c8842415c..d3733912adb4 100644 --- a/arch/powerpc/mm/slb.c +++ b/arch/powerpc/mm/slb.c @@ -22,6 +22,8 @@ #include <asm/paca.h> #include <asm/cputable.h> #include <asm/cacheflush.h> +#include <asm/smp.h> +#include <linux/compiler.h> #ifdef DEBUG #define DBG(fmt...) udbg_printf(fmt) @@ -50,9 +52,32 @@ static inline unsigned long mk_vsid_data(unsigned long ea, unsigned long flags) return (get_kernel_vsid(ea) << SLB_VSID_SHIFT) | flags; } -static inline void create_slbe(unsigned long ea, unsigned long flags, - unsigned long entry) +static inline void slb_shadow_update(unsigned long esid, unsigned long vsid, + unsigned long entry) { + /* + * Clear the ESID first so the entry is not valid while we are + * updating it. + */ + get_slb_shadow()->save_area[entry].esid = 0; + barrier(); + get_slb_shadow()->save_area[entry].vsid = vsid; + barrier(); + get_slb_shadow()->save_area[entry].esid = esid; + +} + +static inline void create_shadowed_slbe(unsigned long ea, unsigned long flags, + unsigned long entry) +{ + /* + * Updating the shadow buffer before writing the SLB ensures + * we don't get a stale entry here if we get preempted by PHYP + * between these two statements. + */ + slb_shadow_update(mk_esid_data(ea, entry), mk_vsid_data(ea, flags), + entry); + asm volatile("slbmte %0,%1" : : "r" (mk_vsid_data(ea, flags)), "r" (mk_esid_data(ea, entry)) @@ -77,6 +102,10 @@ void slb_flush_and_rebolt(void) if ((ksp_esid_data & ESID_MASK) == PAGE_OFFSET) ksp_esid_data &= ~SLB_ESID_V; + /* Only third entry (stack) may change here so only resave that */ + slb_shadow_update(ksp_esid_data, + mk_vsid_data(ksp_esid_data, lflags), 2); + /* We need to do this all in asm, so we're sure we don't touch * the stack between the slbia and rebolting it. */ asm volatile("isync\n" @@ -209,9 +238,9 @@ void slb_initialize(void) asm volatile("isync":::"memory"); asm volatile("slbmte %0,%0"::"r" (0) : "memory"); asm volatile("isync; slbia; isync":::"memory"); - create_slbe(PAGE_OFFSET, lflags, 0); + create_shadowed_slbe(PAGE_OFFSET, lflags, 0); - create_slbe(VMALLOC_START, vflags, 1); + create_shadowed_slbe(VMALLOC_START, vflags, 1); /* We don't bolt the stack for the time being - we're in boot, * so the stack is in the bolted segment. By the time it goes |