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| author | Christophe Leroy <christophe.leroy@csgroup.eu> | 2021-12-24 11:07:40 +0000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2022-02-12 22:47:42 +1100 |
| commit | f222ab83df92acf72691a2021e1f0d99880dcdf1 (patch) | |
| tree | 27c369721e908d9614b72de07a7950ab1c5ecbae /arch/powerpc/include | |
| parent | a4c182ecf33584b9b2d1aa9dad073014a504c01f (diff) | |
| download | linux-f222ab83df92acf72691a2021e1f0d99880dcdf1.tar.gz linux-f222ab83df92acf72691a2021e1f0d99880dcdf1.tar.bz2 linux-f222ab83df92acf72691a2021e1f0d99880dcdf1.zip | |
powerpc: Add set_memory_{p/np}() and remove set_memory_attr()
set_memory_attr() was implemented by commit 4d1755b6a762 ("powerpc/mm:
implement set_memory_attr()") because the set_memory_xx() couldn't
be used at that time to modify memory "on the fly" as explained it
the commit.
But set_memory_attr() uses set_pte_at() which leads to warnings when
CONFIG_DEBUG_VM is selected, because set_pte_at() is unexpected for
updating existing page table entries.
The check could be bypassed by using __set_pte_at() instead,
as it was the case before commit c988cfd38e48 ("powerpc/32:
use set_memory_attr()") but since commit 9f7853d7609d ("powerpc/mm:
Fix set_memory_*() against concurrent accesses") it is now possible
to use set_memory_xx() functions to update page table entries
"on the fly" because the update is now atomic.
For DEBUG_PAGEALLOC we need to clear and set back _PAGE_PRESENT.
Add set_memory_np() and set_memory_p() for that.
Replace all uses of set_memory_attr() by the relevant set_memory_xx()
and remove set_memory_attr().
Fixes: c988cfd38e48 ("powerpc/32: use set_memory_attr()")
Cc: stable@vger.kernel.org
Reported-by: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Tested-by: Maxime Bizon <mbizon@freebox.fr>
Reviewed-by: Russell Currey <ruscur@russell.cc>
Depends-on: 9f7853d7609d ("powerpc/mm: Fix set_memory_*() against concurrent accesses")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/cda2b44b55c96f9ac69fa92e68c01084ec9495c5.1640344012.git.christophe.leroy@csgroup.eu
Diffstat (limited to 'arch/powerpc/include')
| -rw-r--r-- | arch/powerpc/include/asm/set_memory.h | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/arch/powerpc/include/asm/set_memory.h b/arch/powerpc/include/asm/set_memory.h index b040094f7920..7ebc807aa8cc 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_NP 4 /* Set memory non present */ +#define SET_MEMORY_P 5 /* Set memory present */ int change_memory_attr(unsigned long addr, int numpages, long action); @@ -29,6 +31,14 @@ static inline int set_memory_x(unsigned long addr, int numpages) return change_memory_attr(addr, numpages, SET_MEMORY_X); } -int set_memory_attr(unsigned long addr, int numpages, pgprot_t prot); +static inline int set_memory_np(unsigned long addr, int numpages) +{ + return change_memory_attr(addr, numpages, SET_MEMORY_NP); +} + +static inline int set_memory_p(unsigned long addr, int numpages) +{ + return change_memory_attr(addr, numpages, SET_MEMORY_P); +} #endif |