Michael Ellerman's on August 19, 2019 12:00 pm:
> Nicholas Piggin <npig...@gmail.com> writes:
>> Rather than sprinkle various translation structure invalidations
>> around different places in early boot, have each CPU flush everything
>> from its local translation structures before enabling its MMU.
>>
>> Radix guests can execute tlbie(l), so have them tlbiel_all in the same
>> place as radix host does.
>>
>> Signed-off-by: Nicholas Piggin <npig...@gmail.com>
>> ---
>> arch/powerpc/mm/book3s64/radix_pgtable.c | 11 ++---------
>> 1 file changed, 2 insertions(+), 9 deletions(-)
>>
>> diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c
>> b/arch/powerpc/mm/book3s64/radix_pgtable.c
>> index d60cfa05447a..839e01795211 100644
>> --- a/arch/powerpc/mm/book3s64/radix_pgtable.c
>> +++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
>> @@ -382,11 +382,6 @@ static void __init radix_init_pgtable(void)
>> */
>> register_process_table(__pa(process_tb), 0, PRTB_SIZE_SHIFT - 12);
>> pr_info("Process table %p and radix root for kernel: %p\n", process_tb,
>> init_mm.pgd);
>> - asm volatile("ptesync" : : : "memory");
>> - asm volatile(PPC_TLBIE_5(%0,%1,2,1,1) : :
>> - "r" (TLBIEL_INVAL_SET_LPID), "r" (0));
>> - asm volatile("eieio; tlbsync; ptesync" : : : "memory");
>> - trace_tlbie(0, 0, TLBIEL_INVAL_SET_LPID, 0, 2, 1, 1);
>>
>> /*
>> * The init_mm context is given the first available (non-zero) PID,
>> @@ -633,8 +628,7 @@ void __init radix__early_init_mmu(void)
>> radix_init_pgtable();
>> /* Switch to the guard PID before turning on MMU */
>> radix__switch_mmu_context(NULL, &init_mm);
>> - if (cpu_has_feature(CPU_FTR_HVMODE))
>> - tlbiel_all();
>> + tlbiel_all();
>> }
>
> This is oopsing for me in a guest on Power9:
>
> [ 0.000000] radix-mmu: Page sizes from device-tree:
> [ 0.000000] radix-mmu: Page size shift = 12 AP=0x0
> [ 0.000000] radix-mmu: Page size shift = 16 AP=0x5
> [ 0.000000] radix-mmu: Page size shift = 21 AP=0x1
> [ 0.000000] radix-mmu: Page size shift = 30 AP=0x2
> [ 0.000000] -> fw_vec5_feature_init()
> [ 0.000000] <- fw_vec5_feature_init()
> [ 0.000000] -> fw_hypertas_feature_init()
> [ 0.000000] <- fw_hypertas_feature_init()
> [ 0.000000] radix-mmu: Activating Kernel Userspace Execution Prevention
> [ 0.000000] radix-mmu: Activating Kernel Userspace Access Prevention
> [ 0.000000] lpar: Using radix MMU under hypervisor
> [ 0.000000] radix-mmu: Mapped 0x0000000000000000-0x0000000040000000 with
> 1.00 GiB pages (exec)
> [ 0.000000] radix-mmu: Mapped 0x0000000040000000-0x0000000100000000 with
> 1.00 GiB pages
> [ 0.000000] radix-mmu: Process table (____ptrval____) and radix root for
> kernel: (____ptrval____)
> [ 0.000000] Oops: Exception in kernel mode, sig: 4 [#1]
> [ 0.000000] LE PAGE_SIZE=64K MMU=Radix MMU=Hash SMP NR_CPUS=2048 NUMA
> [ 0.000000] Modules linked in:
> [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted
> 5.3.0-rc2-gcc-8.2.0-00063-gef906dcf7b75 #633
> [ 0.000000] NIP: c0000000000838f8 LR: c000000001066864 CTR:
> c0000000000838c0
> [ 0.000000] REGS: c000000001647c40 TRAP: 0700 Not tainted
> (5.3.0-rc2-gcc-8.2.0-00063-gef906dcf7b75)
> [ 0.000000] MSR: 8000000000043003 <SF,FP,ME,RI,LE> CR: 48000222 XER:
> 20040000
> [ 0.000000] CFAR: c0000000000839b4 IRQMASK: 1
> [ 0.000000] GPR00: c000000001066864 c000000001647ed0 c000000001649700
> 0000000000000000
> [ 0.000000] GPR04: c000000001608830 0000000000000000 0000000000000010
> 2000000000000000
> [ 0.000000] GPR08: 0000000000000c00 0000000000000000 0000000000000002
> 726f6620746f6f72
> [ 0.000000] GPR12: c0000000000838c0 c000000001930000 000000000dc5bef0
> 0000000001309e10
> [ 0.000000] GPR16: 0000000001309c90 fffffffffffffffd 000000000dc5bef0
> 0000000001339800
> [ 0.000000] GPR20: 0000000000000014 0000000001ac0000 000000000dc5bf38
> 000000000daf0000
> [ 0.000000] GPR24: 0000000001f4000c c000000000000000 0000000000400000
> c000000001802858
> [ 0.000000] GPR28: c007ffffffffffff c000000001803954 c000000001681cb0
> c000000001608830
> [ 0.000000] NIP [c0000000000838f8] radix__tlbiel_all+0x48/0x110
> [ 0.000000] LR [c000000001066864] radix__early_init_mmu+0x494/0x4c8
> [ 0.000000] Call Trace:
> [ 0.000000] [c000000001647ed0] [c000000001066820]
> radix__early_init_mmu+0x450/0x4c8 (unreliable)
> [ 0.000000] [c000000001647f60] [c00000000105c628] early_setup+0x160/0x198
> [ 0.000000] [c000000001647f90] [000000000000b460] 0xb460
> [ 0.000000] Instruction dump:
> [ 0.000000] 2b830001 39000002 409e00e8 3d220003 3929c318 e9290000
> e9290010 75290002
> [ 0.000000] 41820088 7c4004ac 39200000 79085564 <7d294224> 3940007f
> 39201000 38e00000
> [ 0.000000] random: get_random_bytes called from
> print_oops_end_marker+0x40/0x80 with crng_init=0
> [ 0.000000] ---[ end trace 0000000000000000 ]---
>
>
> So I think we still need a HV check in there somewhere.
Oh it's the partition scope flush by the looks. Simulator doesn't seem
to be trapping that one.
I'll resend, have to fix the kernel invalidation to also do tlbie for
nest.
Thanks,
Nick
