On Fri, Jul 24, 2015 at 10:56:18AM +0100, Mark Rutland wrote: > On Fri, Jul 24, 2015 at 04:56:59AM +0100, yalin wang wrote: > > > > > On Jul 23, 2015, at 21:03, Catalin Marinas <catalin.mari...@arm.com> > > > wrote: > > > > > > On Thu, Jul 23, 2015 at 07:45:53PM +0800, yalin wang wrote: > > >> A little change to patch_map() function, > > >> use set_fixmap_offset() to make code more clear. > > >> > > >> Signed-off-by: yalin wang <yalin.wang2...@gmail.com> > > >> --- > > >> arch/arm64/kernel/insn.c | 5 ++--- > > >> 1 file changed, 2 insertions(+), 3 deletions(-) > > >> > > >> diff --git a/arch/arm64/kernel/insn.c b/arch/arm64/kernel/insn.c > > >> index dd9671c..7dafd5a 100644 > > >> --- a/arch/arm64/kernel/insn.c > > >> +++ b/arch/arm64/kernel/insn.c > > >> @@ -101,9 +101,8 @@ static void __kprobes *patch_map(void *addr, int > > >> fixmap) > > >> return addr; > > >> > > >> BUG_ON(!page); > > >> - set_fixmap(fixmap, page_to_phys(page)); > > >> - > > >> - return (void *) (__fix_to_virt(fixmap) + (uintaddr & > > >> ~PAGE_MASK)); > > >> + return (void *)set_fixmap_offset(fixmap, page_to_phys(page) + > > >> + (addr & ~PAGE_MASK)); > > > > > > It looks fine. Do you get any compiler warning for the automatic pointer > > > to long conversion? You may want to add some explicit casts, otherwise: > > > > > > Acked-by: Catalin Marinas <catalin.mari...@arm.com> > > i have build it, there is no warning about this change. :) > > I see no warnings with defconfig, but there's an (unrelated) set of warnings > if > CONFIG_DEBUG_SET_MODULE_RONX or CONFIG_DEBUG_RODATA are enabled:
Actually they aren't unrelated after all. the unsigned long addr in __set_fixmap_offset shadows the void* addr from patch_map making the types match. With a few underscores addrd to __set_fixmap_offset's addr, I get the following regarding patch_map: ---- In file included from ./arch/arm64/include/asm/fixmap.h:85:0, from arch/arm64/kernel/insn.c:32: arch/arm64/kernel/insn.c: In function ‘patch_map’: arch/arm64/kernel/insn.c:105:10: error: invalid operands to binary & (have ‘void *’ and ‘long unsigned int’) (addr & ~PAGE_MASK)); ^ include/asm-generic/fixmap.h:73:20: note: in definition of macro ‘__set_fixmap_offset’ __set_fixmap(idx, phys, flags); \ ^ arch/arm64/kernel/insn.c:104:17: note: in expansion of macro ‘set_fixmap_offset’ return (void *)set_fixmap_offset(fixmap, page_to_phys(page) + ^ arch/arm64/kernel/insn.c:105:10: error: invalid operands to binary & (have ‘void *’ and ‘long unsigned int’) (addr & ~PAGE_MASK)); ^ include/asm-generic/fixmap.h:74:32: note: in definition of macro ‘__set_fixmap_offset’ __addr = fix_to_virt(idx) + ((phys) & (PAGE_SIZE - 1)); \ ^ arch/arm64/kernel/insn.c:104:17: note: in expansion of macro ‘set_fixmap_offset’ return (void *)set_fixmap_offset(fixmap, page_to_phys(page) + ^ make[1]: *** [arch/arm64/kernel/insn.o] Error 1 make: *** [arch/arm64/kernel/insn.o] Error 2 ---- we need both the cast in patch_map, and an update to __set_fixmap_offset to prevent the name clash. Thanks, Mark. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/