A little change to patch_map() function,
use set_fixmap_offset() to make code more clear.
Signed-off-by: yalin wang <[email protected]>
---
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));
}
static void __kprobes patch_unmap(int fixmap)
--
1.9.1
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 <[email protected]>
> ---
> 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 <[email protected]>
On 07/23/2015 04:45 AM, yalin wang wrote:
> A little change to patch_map() function,
> use set_fixmap_offset() to make code more clear.
>
> Signed-off-by: yalin wang <[email protected]>
> ---
> 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));
> }
>
> static void __kprobes patch_unmap(int fixmap)
>
Reviewed-by: Laura Abbott <[email protected]>
> On Jul 23, 2015, at 21:03, Catalin Marinas <[email protected]> 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 <[email protected]>
>> ---
>> 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 <[email protected]>
i have build it, there is no warning about this change. :)
Thanks-
On Fri, Jul 24, 2015 at 04:56:59AM +0100, yalin wang wrote:
>
> > On Jul 23, 2015, at 21:03, Catalin Marinas <[email protected]> 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 <[email protected]>
> >> ---
> >> 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 <[email protected]>
> 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:
----
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 ‘__aarch64_insn_write’:
include/asm-generic/fixmap.h:73:2: warning: ‘addr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
__set_fixmap(idx, phys, flags); \
^
include/asm-generic/fixmap.h:72:16: note: ‘addr’ was declared here
unsigned long addr; \
^
include/asm-generic/fixmap.h:79:2: note: in expansion of macro ‘__set_fixmap_offset’
__set_fixmap_offset(idx, phys, FIXMAP_PAGE_NORMAL)
^
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) +
^
----
That seems to be due to the definition of __set_fixmap_offset in
asm-generic/fixmap.h:
/* Return a pointer with offset calculated */
#define __set_fixmap_offset(idx, phys, flags) \
({ \
unsigned long addr; \
__set_fixmap(idx, phys, flags); \
addr = fix_to_virt(idx) + ((phys) & (PAGE_SIZE - 1)); \
addr; \
})
Where that new addr variable shadows patch_map's addr argument when the call to
__set_fixmap is expanded.
Which means that this patch currently breaks CONFIG_DEBUG_SET_MODULE_RONX and
CONFIG_DEBUG_RODATA.
Thanks,
Mark.
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 <[email protected]> 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 <[email protected]>
> > >> ---
> > >> 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 <[email protected]>
> > 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.
A little change to patch_map() function,
use set_fixmap_offset() to make code more clear.
Signed-off-by: yalin wang <[email protected]>
---
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..f341866 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) +
+ (uintaddr & ~PAGE_MASK));
}
static void __kprobes patch_unmap(int fixmap)
--
1.9.1
> ?? 2015??7??24?գ?18:07??Mark Rutland <[email protected]> д????
>
> 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 <[email protected]> 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 <[email protected]>
>>>>> ---
>>>>> 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 <[email protected]>
>>> 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.
i see, i will send V2 to solve this.
Thanks-
> On Jul 24, 2015, at 19:52, yalin wang <[email protected]> wrote:
>
> A little change to patch_map() function,
> use set_fixmap_offset() to make code more clear.
>
> Signed-off-by: yalin wang <[email protected]>
> ---
> 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..f341866 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) +
> + (uintaddr & ~PAGE_MASK));
> }
>
> static void __kprobes patch_unmap(int fixmap)
> --
> 1.9.1
>
Marinas,
this V2 patch can build without warning even CONFIG_DEBUG_SET_MODULE_RONX enabled,
could you review it.
Thanks.
On Tue, Jul 28, 2015 at 07:31:20AM +0100, yalin wang wrote:
>
> > On Jul 24, 2015, at 19:52, yalin wang <[email protected]> wrote:
> >
> > A little change to patch_map() function,
> > use set_fixmap_offset() to make code more clear.
> >
> > Signed-off-by: yalin wang <[email protected]>
> > ---
> > 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..f341866 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) +
> > + (uintaddr & ~PAGE_MASK));
> > }
> >
> > static void __kprobes patch_unmap(int fixmap)
> > --
> > 1.9.1
> >
> Marinas,
> this V2 patch can build without warning even CONFIG_DEBUG_SET_MODULE_RONX enabled,
> could you review it.
> Thanks.
I queued this already for 4.3. There's a (benign) sparse warning about the
addr parameter to patch_map being overridden by the local scope of
set_fixmap_offset which could be solved with a healthy portion of
underscores in the core code.
Will