Hi all
I try changing the kernel_execve() function as suggested, but it fails,
I am using code sourcery toolchain 4.4.1 but it still fails. I am
using 2.6.30.9 kernel and this function is part of it.
Kind regards
On Thu, Jan 27, 2011 at 11:14 PM, David Daney <ddaney@xxxxxxxxxxxxxxxxxx> wrote:
> 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.
>>>>>
>>>>>
>>>>
>>>>
>>>
>>>
>>
>
>
