On 01/27/2011 07:18 AM, adnan iqbal wrote:
> Please try this. One line of code is added ( move %1, $7).
>
>
> int kernel_execve(const char *filename, char *const argv[], char *const
> envp[])
> {
> register unsigned long __a0 asm("$4") = (unsigned long) filename;
> register unsigned long __a1 asm("$5") = (unsigned long) argv;
> register unsigned long __a2 asm("$6") = (unsigned long) envp;
> register unsigned long __a3 asm("$7");
> unsigned long __v0;
> __asm__ volatile (" \n"
> " .set noreorder \n"
> " li $2, %5 # __NR_execve \n"
> " syscall \n"
> " move %0, $2 \n"
> " move %1, $7 \n"
> " .set reorder \n"
> : "=&r" (__v0), "=r" (__a3)
> : "r" (__a0), "r" (__a1), "r" (__a2), "i" (__NR_execve)
> : "$2", "$8", "$9", "$10", "$11", "$12", "$13", "$14", "$15", "$24",
> "memory");
>
>
> if (__a3 == 0)
> return __v0;
> return -__v0;
> }
>
I don't know where you got that code. But really you should do what
glibc does. glibc gets it correct.
At a minimum you are missing "hi" and "lo" clobbers.
If the code works with 16K pages, and not 64K pages, then this snippet
is not the problem. Likely your problem is the layout of the PHDRs in
the executable is not compatible with the page size.
David Daney
>
> On Thu, Jan 27, 2011 at 7:55 PM, naveen yadav<yad.naveen@xxxxxxxxx> wrote:
>
>> Hi David,
>>
>> thanks for your response.
>>
>> I check and found that kernel is booting with 16KB page size with
>> ramdisk booting. But when I change to 64KB it give me
>>
>> : applet not found
>> Kernel panic - not syncing: Attempted to kill init!
>> so I check and found that it is not able to execute well the system
>> call in kernel_execve function.
>> I am using codesourcercy toolchain(4.3.1). So is there a way to debug
>> this problem or how to debug below function.
>>
>> int kernel_execve(const char *filename, char *const argv[], char *const
>> envp[])
>> {
>> register unsigned long __a0 asm("$4") = (unsigned long) filename;
>> register unsigned long __a1 asm("$5") = (unsigned long) argv;
>> register unsigned long __a2 asm("$6") = (unsigned long) envp;
>> register unsigned long __a3 asm("$7");
>> unsigned long __v0;
>> __asm__ volatile (" \n"
>> " .set noreorder \n"
>> " li $2, %5 # __NR_execve \n"
>> " syscall \n"
>> " move %0, $2 \n"
>> " .set reorder \n"
>> : "=&r" (__v0), "=r" (__a3)
>> : "r" (__a0), "r" (__a1), "r" (__a2), "i" (__NR_execve)
>> : "$2", "$8", "$9", "$10", "$11", "$12", "$13", "$14", "$15", "$24",
>> "memory");
>>
>>
>> if (__a3 == 0)
>> return __v0;
>> return -__v0;
>> }
>>
>>
>> On Tue, Jan 25, 2011 at 12:26 AM, David Daney<ddaney@xxxxxxxxxxxxxxxxxx>
>> wrote:
>>> On 01/24/2011 07:02 AM, naveen yadav wrote:
>>>>
>>>> Hi All,
>>>>
>>>>
>>>> we are using mips32r2 so I want to know which all pages size it can
>>>> support?
>>>> When I modify arch/mips/Kconfig. it boot sucessfully on 16KB page
>>>> size. but hang/not boot crash when change page size to 8KB,32KB and 64
>>>> KB.
>>>
>>> I don't think 8KB and 32KB work on most mips32r2 processors. You would
>> have
>>> to check the processor manual to be sure.
>>>
>>>
>>>>
>>>> We are using 2.6.30 kernel.
>>>>
>>>> At Page Size 8KB and 32KB it hang in unpack_to_rootfs() function of
>>>> init/initramfs.c
>>>>
>>>> 64KB it hangs when execute init Kernel panic - not syncing: Attempted
>>>> to kill init!
>>>
>>> I regularly run 4K, 16K, and 64K page sizes with a Debian rootfs. If you
>>> run with a broken uClibc toolchain that doesn't support larger pages, it
>>> will of course fail. In this case the problem is with your toolchain,
>> not
>>> the kernel.
>>>
>>> David Daney
>>>
>>>
>>>>
>>>> config PAGE_SIZE_4KB
>>>> bool "4kB"
>>>> help
>>>> This option select the standard 4kB Linux page size. On some
>>>> R3000-family processors this is the only available page size.
>>>> Using
>>>> 4kB page size will minimize memory consumption and is therefore
>>>> recommended for low memory systems.
>>>>
>>>> config PAGE_SIZE_8KB
>>>> bool "8kB"
>>>> depends on (EXPERIMENTAL&& CPU_R8000) || CPU_CAVIUM_OCTEON
>>>> help
>>>> Using 8kB page size will result in higher performance kernel
>> at
>>>> the price of higher memory consumption. This option is
>>>> available
>>>> only on R8000 and cnMIPS processors. Note that you will need
>> a
>>>> suitable Linux distribution to support this.
>>>>
>>>> config PAGE_SIZE_16KB
>>>> bool "16kB"
>>>> depends on !CPU_R3000&& !CPU_TX39XX
>>>> help
>>>> Using 16kB page size will result in higher performance kernel
>> at
>>>> the price of higher memory consumption. This option is
>>>> available on
>>>> all non-R3000 family processors. Note that you will need a
>>>> suitable
>>>> Linux distribution to support this.
>>>>
>>>> config PAGE_SIZE_32KB
>>>> bool "32kB"
>>>> help
>>>> Using 32kB page size will result in higher performance kernel
>> at
>>>> the price of higher memory consumption. This option is
>>>> available
>>>> only on cnMIPS cores. Note that you will need a suitable
>> Linux
>>>> distribution to support this.
>>>>
>>>> config PAGE_SIZE_64KB
>>>> bool "64kB"
>>>> depends on EXPERIMENTAL&& !CPU_R3000&& !CPU_TX39XX
>>>> help
>>>> Using 64kB page size will result in higher performance kernel
>> at
>>>> the price of higher memory consumption. This option is
>>>> available on
>>>> all non-R3000 family processor. Not that at the time of this
>>>> writing this option is still high experimental.
>>>>
>>>>
>>>
>>>
>>
>>
>
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