| Message ID | 18906.50854.952483.793456@drongo.ozlabs.ibm.com (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Commit | 11b55da700eb77905f1c2dde3a0cbeedc665a753 |
| Delegated to: | Paul Mackerras |
| Headers | show |
On Tue, 7 Apr 2009, Paul Mackerras wrote: > This fixes a problem reported by Sean MacLennan where loading any > module would cause an oops. We weren't marking the pages containing > the module text as having hardware execute permission, due to a bug > introduced in commit 8d1cf34e ("powerpc/mm: Tweak PTE bit combination > definitions"), hence trying to execute the module text caused an > exception on processors that support hardware execute permission. > > This adds _PAGE_HWEXEC to the definitions of PAGE_KERNEL_X and > PAGE_KERNEL_ROX to fix this problem. > > Reported-by: Sean MacLennan <smaclennan@pikatech.com> > Signed-off-by: Paul Mackerras <paulus@samba.org> Tested-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com> (on Sequoia) With kind regards, Geert Uytterhoeven Software Architect Sony Techsoft Centre Europe The Corporate Village · Da Vincilaan 7-D1 · B-1935 Zaventem · Belgium Phone: +32 (0)2 700 8453 Fax: +32 (0)2 700 8622 E-mail: Geert.Uytterhoeven@sonycom.com Internet: http://www.sony-europe.com/ A division of Sony Europe (Belgium) N.V. VAT BE 0413.825.160 · RPR Brussels Fortis · BIC GEBABEBB · IBAN BE41293037680010
diff --git a/arch/powerpc/include/asm/pte-common.h b/arch/powerpc/include/asm/pte-common.h index d9740e8..a7e210b 100644 --- a/arch/powerpc/include/asm/pte-common.h +++ b/arch/powerpc/include/asm/pte-common.h @@ -151,9 +151,11 @@ extern unsigned long bad_call_to_PMD_PAGE_SIZE(void); _PAGE_NO_CACHE) #define PAGE_KERNEL_NCG __pgprot(_PAGE_BASE_NC | _PAGE_KERNEL_RW | \ _PAGE_NO_CACHE | _PAGE_GUARDED) -#define PAGE_KERNEL_X __pgprot(_PAGE_BASE | _PAGE_KERNEL_RW | _PAGE_EXEC) +#define PAGE_KERNEL_X __pgprot(_PAGE_BASE | _PAGE_KERNEL_RW | _PAGE_EXEC | \ + _PAGE_HWEXEC) #define PAGE_KERNEL_RO __pgprot(_PAGE_BASE | _PAGE_KERNEL_RO) -#define PAGE_KERNEL_ROX __pgprot(_PAGE_BASE | _PAGE_KERNEL_RO | _PAGE_EXEC) +#define PAGE_KERNEL_ROX __pgprot(_PAGE_BASE | _PAGE_KERNEL_RO | _PAGE_EXEC | \ + _PAGE_HWEXEC) /* Protection used for kernel text. We want the debuggers to be able to * set breakpoints anywhere, so don't write protect the kernel text
This fixes a problem reported by Sean MacLennan where loading any module would cause an oops. We weren't marking the pages containing the module text as having hardware execute permission, due to a bug introduced in commit 8d1cf34e ("powerpc/mm: Tweak PTE bit combination definitions"), hence trying to execute the module text caused an exception on processors that support hardware execute permission. This adds _PAGE_HWEXEC to the definitions of PAGE_KERNEL_X and PAGE_KERNEL_ROX to fix this problem. Reported-by: Sean MacLennan <smaclennan@pikatech.com> Signed-off-by: Paul Mackerras <paulus@samba.org> --- arch/powerpc/include/asm/pte-common.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)