On Fri, 3 Aug 2018 14:13:49 +1000
Nicholas Piggin <npig...@gmail.com> wrote:
> The machine check code that flushes and restores bolted segments in
> real mode belongs in mm/slb.c. This will be used by pseries machine
> check and idle code.
>
> Signed-off-by: Nicholas Piggin <npig...@gmail.com>
> ---
> arch/powerpc/include/asm/book3s/64/mmu-hash.h | 3 ++
> arch/powerpc/kernel/mce_power.c | 21 ++--------
> arch/powerpc/mm/slb.c | 38
> +++++++++++++++++++ 3 files changed, 44 insertions(+), 18 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/book3s/64/mmu-hash.h
> b/arch/powerpc/include/asm/book3s/64/mmu-hash.h index
> 2f74bdc805e0..d4e398185b3a 100644 ---
> a/arch/powerpc/include/asm/book3s/64/mmu-hash.h +++
> b/arch/powerpc/include/asm/book3s/64/mmu-hash.h @@ -497,6 +497,9 @@
> extern void hpte_init_native(void);
> extern void slb_initialize(void);
> extern void slb_flush_and_rebolt(void);
> +extern void slb_flush_all_realmode(void);
> +extern void __slb_restore_bolted_realmode(void);
> +extern void slb_restore_bolted_realmode(void);
>
> extern void slb_vmalloc_update(void);
> extern void slb_set_size(u16 size);
> diff --git a/arch/powerpc/kernel/mce_power.c
> b/arch/powerpc/kernel/mce_power.c index d6756af6ec78..50f7b9817246
> 100644 --- a/arch/powerpc/kernel/mce_power.c
> +++ b/arch/powerpc/kernel/mce_power.c
> @@ -62,11 +62,8 @@ static unsigned long addr_to_pfn(struct pt_regs
> *regs, unsigned long addr) #ifdef CONFIG_PPC_BOOK3S_64
> static void flush_and_reload_slb(void)
> {
> - struct slb_shadow *slb;
> - unsigned long i, n;
> -
> /* Invalidate all SLBs */
> - asm volatile("slbmte %0,%0; slbia" : : "r" (0));
> + slb_flush_all_realmode();
>
> #ifdef CONFIG_KVM_BOOK3S_HANDLER
> /*
> @@ -76,22 +73,10 @@ static void flush_and_reload_slb(void)
> if (get_paca()->kvm_hstate.in_guest)
> return;
> #endif
> -
> - /* For host kernel, reload the SLBs from shadow SLB buffer.
> */
> - slb = get_slb_shadow();
> - if (!slb)
> + if (early_radix_enabled())
> return;
And we lose the check that the shadow slb exists. Is !slb equivalent to
early_radix_enabled()
>
> - n = min_t(u32, be32_to_cpu(slb->persistent), SLB_MIN_SIZE);
> -
> - /* Load up the SLB entries from shadow SLB */
> - for (i = 0; i < n; i++) {
> - unsigned long rb =
> be64_to_cpu(slb->save_area[i].esid);
> - unsigned long rs =
> be64_to_cpu(slb->save_area[i].vsid); -
> - rb = (rb & ~0xFFFul) | i;
> - asm volatile("slbmte %0,%1" : : "r" (rs), "r" (rb));
> - }
> + slb_restore_bolted_realmode();
> }
> #endif
>
> diff --git a/arch/powerpc/mm/slb.c b/arch/powerpc/mm/slb.c
> index cb796724a6fc..136db8652577 100644
> --- a/arch/powerpc/mm/slb.c
> +++ b/arch/powerpc/mm/slb.c
> @@ -90,6 +90,44 @@ static inline void create_shadowed_slbe(unsigned
> long ea, int ssize, : "memory" );
> }
>
> +/*
> + * Insert bolted entries into SLB (which may not be empty).
> + */
> +void __slb_restore_bolted_realmode(void)
> +{
> + struct slb_shadow *p = get_slb_shadow();
> + enum slb_index index;
or can we get here at some point when shadow slb is not populated?
Thanks
Michal
> +
> + /* No isync needed because realmode. */
> + for (index = 0; index < SLB_NUM_BOLTED; index++) {
> + asm volatile("slbmte %0,%1" :
> + : "r" (be64_to_cpu(p->save_area[index].vsid)),
> + "r" (be64_to_cpu(p->save_area[index].esid)));
> + }
> +}
> +
> +/*
> + * Insert bolted entries into an empty SLB.
> + * This is not the same as rebolt because the bolted segments
> + * (e.g., kstack) are not changed (rebolted).
> + */
> +void slb_restore_bolted_realmode(void)
> +{
> + __slb_restore_bolted_realmode();
> + get_paca()->slb_cache_ptr = 0;
> +}
> +
> +/*
> + * This flushes all SLB entries including 0, so it must be realmode.
> + */
> +void slb_flush_all_realmode(void)
> +{
> + /*
> + * This flushes all SLB entries including 0, so it must be
> realmode.
> + */
> + asm volatile("slbmte %0,%0; slbia" : : "r" (0));
> +}
> +
> static void __slb_flush_and_rebolt(void)
> {
> /* If you change this make sure you change SLB_NUM_BOLTED
