diff options
| author | Aneesh Kumar K.V (IBM) <aneesh.kumar@kernel.org> | 2023-12-04 15:06:37 +0530 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2023-12-07 23:34:11 +1100 |
| commit | 773b93f1d1c38c5c0d5308b8c9229c7a6ec5b2a0 (patch) | |
| tree | 324ada961a6bcad350dc738ed3e8523ab6dd12ac /arch/powerpc | |
| parent | 27951e1d8274e9f9a2925b069e4492939a3f2099 (diff) | |
powerpc/book3s/hash: Drop _PAGE_PRIVILEGED from PAGE_NONE
There used to be a dependency on _PAGE_PRIVILEGED with pte_savedwrite.
But that got dropped by
commit 6a56ccbcf6c6 ("mm/autonuma: use can_change_(pte|pmd)_writable() to replace savedwrite")
With the change in this patch numa fault pte (pte_protnone()) gets mapped as regular user pte
with RWX cleared (no-access) whereas earlier it used to be mapped _PAGE_PRIVILEGED.
Hash fault handling code gets some WARN_ON added in this patch because
those functions are not expected to get called with _PAGE_READ cleared.
commit 18061c17c8ec ("powerpc/mm: Update PROTFAULT handling in the page
fault path") explains the details.
Signed-off-by: "Aneesh Kumar K.V (IBM)" <aneesh.kumar@kernel.org>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231204093638.71503-1-aneesh.kumar@kernel.org
Diffstat (limited to 'arch/powerpc')
| -rw-r--r-- | arch/powerpc/include/asm/book3s/64/pgtable.h | 10 | ||||
| -rw-r--r-- | arch/powerpc/mm/book3s64/hash_utils.c | 7 |
2 files changed, 9 insertions, 8 deletions
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h index cb77eddca54b..927d585652bc 100644 --- a/arch/powerpc/include/asm/book3s/64/pgtable.h +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h @@ -17,12 +17,6 @@ #define _PAGE_EXEC 0x00001 /* execute permission */ #define _PAGE_WRITE 0x00002 /* write access allowed */ #define _PAGE_READ 0x00004 /* read access allowed */ -#define _PAGE_NA _PAGE_PRIVILEGED -#define _PAGE_NAX _PAGE_EXEC -#define _PAGE_RO _PAGE_READ -#define _PAGE_ROX (_PAGE_READ | _PAGE_EXEC) -#define _PAGE_RW (_PAGE_READ | _PAGE_WRITE) -#define _PAGE_RWX (_PAGE_READ | _PAGE_WRITE | _PAGE_EXEC) #define _PAGE_PRIVILEGED 0x00008 /* kernel access only */ #define _PAGE_SAO 0x00010 /* Strong access order */ #define _PAGE_NON_IDEMPOTENT 0x00020 /* non idempotent memory */ @@ -532,8 +526,8 @@ static inline bool pte_user(pte_t pte) static inline bool pte_access_permitted(pte_t pte, bool write) { /* - * _PAGE_READ is needed for any access and will be - * cleared for PROT_NONE + * _PAGE_READ is needed for any access and will be cleared for + * PROT_NONE. Execute-only mapping via PROT_EXEC also returns false. */ if (!pte_present(pte) || !pte_user(pte) || !pte_read(pte)) return false; diff --git a/arch/powerpc/mm/book3s64/hash_utils.c b/arch/powerpc/mm/book3s64/hash_utils.c index ad2afa08e62e..0626a25b0d72 100644 --- a/arch/powerpc/mm/book3s64/hash_utils.c +++ b/arch/powerpc/mm/book3s64/hash_utils.c @@ -310,9 +310,16 @@ unsigned long htab_convert_pte_flags(unsigned long pteflags, unsigned long flags else rflags |= 0x3; } + VM_WARN_ONCE(!(pteflags & _PAGE_RWX), "no-access mapping request"); } else { if (pteflags & _PAGE_RWX) rflags |= 0x2; + /* + * We should never hit this in normal fault handling because + * a permission check (check_pte_access()) will bubble this + * to higher level linux handler even for PAGE_NONE. + */ + VM_WARN_ONCE(!(pteflags & _PAGE_RWX), "no-access mapping request"); if (!((pteflags & _PAGE_WRITE) && (pteflags & _PAGE_DIRTY))) rflags |= 0x1; } |