RE: [V2,10/68] powerpc/mm: Update _PAGE_KERNEL_RO
From: Geoff Levand <geoff@infradead.org>
Date: 2016-11-20 00:43:50
Hi Aneesh,
quoted hunk ↗ jump to hunk
--- a/arch/powerpc/platforms/ps3/spu.c +++ b/arch/powerpc/platforms/ps3/spu.c@@ -205,7 +205,7 @@ static void spu_unmap(struct spu *spu) static int __init setup_areas(struct spu *spu) { struct table {char* name; unsigned long addr; unsigned long size;}; - static const unsigned long shadow_flags = _PAGE_NO_CACHE | 3; + unsigned long shadow_flags = pgprot_val(pgprot_noncached_wc(PAGE_KERNEL_RO)); spu_pdata(spu)->shadow = __ioremap(spu_pdata(spu)->shadow_addr, sizeof(struct spe_shadow),
This shadow_flags setting doesn't work correctly for PS3. The PS3's LV1 hypervisor wants the shadow reg pte bits N=1 and PP=11, so (rflags & 7) == 7. It also doesn't want bit 0x8000000000000000 set. So maybe these: (HPTE_R_N | HPTE_R_PP & ~HPTE_R_PP0) For what its worth, this is the error for v4.8: ps3_hpte_insert:result=LV1_ILLEGAL_PARAMETER_VALUE (-17) vpn=7e4fa575c0000 pa=300000003000 ix=bae0 v=7e4fa575c001 r=8000300000003126 I tried different shadow_flags settings to try to get htab_convert_pte_flags() to give me the right pte bits, but couldn't find anything that would work. Here's the only thing I could get to work:
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c@@ -222,6 +222,12 @@ unsigned long htab_convert_pte_flags(unsigned long pteflags) */ rflags |= HPTE_R_M; + if ((pteflags & 0xc000300000000000UL) == 0xc000300000000000UL) { + pr_info("%s: bad rflags: pteflags= %lx => rflags=%lx\n", + __func__, pteflags, rflags); + return 0x127; + } + return rflags; }
And here's the output of that: htab_convert_pte_flags: bad rflags: pteflags= c00030000000393c => rflags=8000000000000126 htab_convert_pte_flags: bad rflags: pteflags= c00030000000593c => rflags=8000000000000126 htab_convert_pte_flags: bad rflags: pteflags= c00030000000793c => rflags=8000000000000126 htab_convert_pte_flags: bad rflags: pteflags= c00030000000993c => rflags=8000000000000126 htab_convert_pte_flags: bad rflags: pteflags= c00030000000b93c => rflags=8000000000000126 htab_convert_pte_flags: bad rflags: pteflags= c00030000000d93c => rflags=8000000000000126 Actually, the problem started with (6a119eae942c "powerpc/mm: Add a _PAGE_PTE bit"), but I could fix that by using 'shadow_flags = (_PAGE_PRESENT | _PAGE_NO_CACHE | _PAGE_USER)'. Please let me know what I need for shadow_flags to get those pte bits set. -Geoff