| Message ID | 20210517061658.194708-2-jniethe5@gmail.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | powerpc/64s: Enable KFENCE | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | warning | Failed to apply on branch powerpc/merge (3a81c0495fdb91fd9a9b4f617098c283131eeae1) |
| snowpatch_ozlabs/apply_patch | warning | Failed to apply on branch powerpc/next (6efb943b8616ec53a5e444193dccf1af9ad627b5) |
| snowpatch_ozlabs/apply_patch | warning | Failed to apply on branch linus/master (d07f6ca923ea0927a1024dfccafc5b53b61cfecc) |
| snowpatch_ozlabs/apply_patch | warning | Failed to apply on branch powerpc/fixes (c6ac667b07996929835b512de0e9a988977e6abc) |
| snowpatch_ozlabs/apply_patch | warning | Failed to apply on branch linux-next (c12a29ed9094b4b9cde8965c12850460b9a79d7c) |
| snowpatch_ozlabs/apply_patch | fail | Failed to apply to any branch |
Jordan Niethe <jniethe5@gmail.com> writes: > There is support for DEBUG_PAGEALLOC on hash but not on radix. > Add support on radix. Somewhat off-topic but I wonder at what point we can drop the weird !PPC condition in mm/Kconfig.debug: config DEBUG_PAGEALLOC bool "Debug page memory allocations" depends on DEBUG_KERNEL depends on !HIBERNATION || ARCH_SUPPORTS_DEBUG_PAGEALLOC && !PPC && !SPARC I can't figure out from git history why it exists or if it still serves any function. Given that HIBERNATION isn't much use on Book3S systems it probably never matters, it just bugs me a bit. Again, nothing that has to block this series, just maybe something to follow up at some vague and undefined point in the future! > diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h > index a666d561b44d..b89482aed82a 100644 > --- a/arch/powerpc/include/asm/book3s/64/pgtable.h > +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h > @@ -812,6 +822,15 @@ static inline bool check_pte_access(unsigned long access, unsigned long ptev) > * Generic functions with hash/radix callbacks > */ > > +#ifdef CONFIG_DEBUG_PAGEALLOC > +static inline void __kernel_map_pages(struct page *page, int numpages, int enable) > +{ > + if (radix_enabled()) > + radix__kernel_map_pages(page, numpages, enable); > + hash__kernel_map_pages(page, numpages, enable); Does this require an else? On radix we will call both radix__ and hash__kernel_map_pages. I notice we call both hash__ and radix__ in map_kernel_page under radix, so maybe this makes sense? I don't fully understand the mechanism by which memory removal works: it looks like on radix you mark the page as 'absent', which I think is enough? Then you fall through to the hash code here: for (i = 0; i < numpages; i++, page++) { vaddr = (unsigned long)page_address(page); lmi = __pa(vaddr) >> PAGE_SHIFT; if (lmi >= linear_map_hash_count) continue; I think linear_map_hash_count will be zero unless it gets inited to a non-zero value in htab_initialize(). I am fairly sure htab_initialize() doesn't get called for a radix MMU. In that case you'll just `continue;` out of every iteration of the loop, which would explain why nothing weird would happen on radix. Have I missed something here? The rest of the patch looks good to me. Kind regards, Daniel
diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h b/arch/powerpc/include/asm/book3s/32/pgtable.h index 83c65845a1a9..30533d409f7f 100644 --- a/arch/powerpc/include/asm/book3s/32/pgtable.h +++ b/arch/powerpc/include/asm/book3s/32/pgtable.h @@ -417,6 +417,16 @@ static inline unsigned long pte_pfn(pte_t pte) } /* Generic modifiers for PTE bits */ +static inline pte_t pte_mkabsent(pte_t pte) +{ + return __pte(pte_val(pte) & ~_PAGE_PRESENT); +} + +static inline pte_t pte_mkpresent(pte_t pte) +{ + return __pte(pte_val(pte) | _PAGE_PRESENT); +} + static inline pte_t pte_wrprotect(pte_t pte) { return __pte(pte_val(pte) & ~_PAGE_RW); diff --git a/arch/powerpc/include/asm/book3s/64/hash.h b/arch/powerpc/include/asm/book3s/64/hash.h index d959b0195ad9..f6171633cdc2 100644 --- a/arch/powerpc/include/asm/book3s/64/hash.h +++ b/arch/powerpc/include/asm/book3s/64/hash.h @@ -179,6 +179,8 @@ static inline unsigned long hash__pte_update(struct mm_struct *mm, return old; } +void hash__kernel_map_pages(struct page *page, int numpages, int enable); + /* Set the dirty and/or accessed bits atomically in a linux PTE, this * function doesn't need to flush the hash entry */ diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h index a666d561b44d..b89482aed82a 100644 --- a/arch/powerpc/include/asm/book3s/64/pgtable.h +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h @@ -651,6 +651,16 @@ static inline unsigned long pte_pfn(pte_t pte) } /* Generic modifiers for PTE bits */ +static inline pte_t pte_mkabsent(pte_t pte) +{ + return __pte_raw(pte_raw(pte) & cpu_to_be64(~_PAGE_PRESENT)); +} + +static inline pte_t pte_mkpresent(pte_t pte) +{ + return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_PRESENT)); +} + static inline pte_t pte_wrprotect(pte_t pte) { if (unlikely(pte_savedwrite(pte))) @@ -812,6 +822,15 @@ static inline bool check_pte_access(unsigned long access, unsigned long ptev) * Generic functions with hash/radix callbacks */ +#ifdef CONFIG_DEBUG_PAGEALLOC +static inline void __kernel_map_pages(struct page *page, int numpages, int enable) +{ + if (radix_enabled()) + radix__kernel_map_pages(page, numpages, enable); + hash__kernel_map_pages(page, numpages, enable); +} +#endif + static inline void __ptep_set_access_flags(struct vm_area_struct *vma, pte_t *ptep, pte_t entry, unsigned long address, diff --git a/arch/powerpc/include/asm/book3s/64/radix.h b/arch/powerpc/include/asm/book3s/64/radix.h index 59cab558e2f0..d4fa28a77cc6 100644 --- a/arch/powerpc/include/asm/book3s/64/radix.h +++ b/arch/powerpc/include/asm/book3s/64/radix.h @@ -137,6 +137,8 @@ extern void radix__mark_rodata_ro(void); extern void radix__mark_initmem_nx(void); #endif +void radix__kernel_map_pages(struct page *page, int numpages, int enable); + extern void radix__ptep_set_access_flags(struct vm_area_struct *vma, pte_t *ptep, pte_t entry, unsigned long address, int psize); diff --git a/arch/powerpc/include/asm/nohash/pgtable.h b/arch/powerpc/include/asm/nohash/pgtable.h index ac75f4ab0dba..2a57bbb5820a 100644 --- a/arch/powerpc/include/asm/nohash/pgtable.h +++ b/arch/powerpc/include/asm/nohash/pgtable.h @@ -125,6 +125,16 @@ static inline unsigned long pte_pfn(pte_t pte) { return pte_val(pte) >> PTE_RPN_SHIFT; } /* Generic modifiers for PTE bits */ +static inline pte_t pte_mkabsent(pte_t pte) +{ + return __pte(pte_val(pte) & ~_PAGE_PRESENT); +} + +static inline pte_t pte_mkpresent(pte_t pte) +{ + return __pte(pte_val(pte) | _PAGE_PRESENT); +} + static inline pte_t pte_exprotect(pte_t pte) { return __pte(pte_val(pte) & ~_PAGE_EXEC); diff --git a/arch/powerpc/include/asm/set_memory.h b/arch/powerpc/include/asm/set_memory.h index b040094f7920..4b6dfaad4cc9 100644 --- a/arch/powerpc/include/asm/set_memory.h +++ b/arch/powerpc/include/asm/set_memory.h @@ -6,6 +6,8 @@ #define SET_MEMORY_RW 1 #define SET_MEMORY_NX 2 #define SET_MEMORY_X 3 +#define SET_MEMORY_EN 4 +#define SET_MEMORY_DIS 5 int change_memory_attr(unsigned long addr, int numpages, long action); diff --git a/arch/powerpc/mm/book3s64/hash_utils.c b/arch/powerpc/mm/book3s64/hash_utils.c index 96d9aa164007..5b9709075fbd 100644 --- a/arch/powerpc/mm/book3s64/hash_utils.c +++ b/arch/powerpc/mm/book3s64/hash_utils.c @@ -1990,7 +1990,7 @@ static void kernel_unmap_linear_page(unsigned long vaddr, unsigned long lmi) mmu_kernel_ssize, 0); } -void __kernel_map_pages(struct page *page, int numpages, int enable) +void hash__kernel_map_pages(struct page *page, int numpages, int enable) { unsigned long flags, vaddr, lmi; int i; diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c index 5fef8db3b463..2aa81b9e354a 100644 --- a/arch/powerpc/mm/book3s64/radix_pgtable.c +++ b/arch/powerpc/mm/book3s64/radix_pgtable.c @@ -16,6 +16,7 @@ #include <linux/hugetlb.h> #include <linux/string_helpers.h> #include <linux/memory.h> +#include <linux/set_memory.h> #include <asm/pgalloc.h> #include <asm/mmu_context.h> @@ -330,9 +331,13 @@ static int __meminit create_physical_mapping(unsigned long start, static void __init radix_init_pgtable(void) { unsigned long rts_field; + unsigned long size = radix_mem_block_size; phys_addr_t start, end; u64 i; + if (debug_pagealloc_enabled()) + size = PAGE_SIZE; + /* We don't support slb for radix */ mmu_slb_size = 0; @@ -352,7 +357,7 @@ static void __init radix_init_pgtable(void) } WARN_ON(create_physical_mapping(start, end, - radix_mem_block_size, + size, -1, PAGE_KERNEL)); } @@ -872,13 +877,18 @@ int __meminit radix__create_section_mapping(unsigned long start, unsigned long end, int nid, pgprot_t prot) { + unsigned long size = radix_mem_block_size; + + if (debug_pagealloc_enabled()) + size = PAGE_SIZE; + if (end >= RADIX_VMALLOC_START) { pr_warn("Outside the supported range\n"); return -1; } return create_physical_mapping(__pa(start), __pa(end), - radix_mem_block_size, nid, prot); + size, nid, prot); } int __meminit radix__remove_section_mapping(unsigned long start, unsigned long end) @@ -1165,3 +1175,15 @@ int pmd_free_pte_page(pmd_t *pmd, unsigned long addr) return 1; } + +#ifdef CONFIG_DEBUG_PAGEALLOC +void radix__kernel_map_pages(struct page *page, int numpages, int enable) +{ + unsigned long addr = (unsigned long)page_address(page); + + if (enable) + change_memory_attr(addr, numpages, SET_MEMORY_EN); + else + change_memory_attr(addr, numpages, SET_MEMORY_DIS); +} +#endif diff --git a/arch/powerpc/mm/pageattr.c b/arch/powerpc/mm/pageattr.c index 0876216ceee6..d3db09447fa6 100644 --- a/arch/powerpc/mm/pageattr.c +++ b/arch/powerpc/mm/pageattr.c @@ -54,6 +54,12 @@ static int change_page_attr(pte_t *ptep, unsigned long addr, void *data) case SET_MEMORY_X: pte = pte_mkexec(pte); break; + case SET_MEMORY_DIS: + pte = pte_mkabsent(pte); + break; + case SET_MEMORY_EN: + pte = pte_mkpresent(pte); + break; default: WARN_ON_ONCE(1); break;
There is support for DEBUG_PAGEALLOC on hash but not on radix. Add support on radix. Signed-off-by: Jordan Niethe <jniethe5@gmail.com> --- arch/powerpc/include/asm/book3s/32/pgtable.h | 10 ++++++++ arch/powerpc/include/asm/book3s/64/hash.h | 2 ++ arch/powerpc/include/asm/book3s/64/pgtable.h | 19 ++++++++++++++ arch/powerpc/include/asm/book3s/64/radix.h | 2 ++ arch/powerpc/include/asm/nohash/pgtable.h | 10 ++++++++ arch/powerpc/include/asm/set_memory.h | 2 ++ arch/powerpc/mm/book3s64/hash_utils.c | 2 +- arch/powerpc/mm/book3s64/radix_pgtable.c | 26 ++++++++++++++++++-- arch/powerpc/mm/pageattr.c | 6 +++++ 9 files changed, 76 insertions(+), 3 deletions(-)