Re: page size change on MIPS
Hi... On Tue, Feb 8, 2011 at 14:35, naveen yadav yad.nav...@gmail.com wrote: Hi All, I debug this issue further, I check in kernel File name is binfmt_elf.c and function name is create_elf_tables() I put a debug print here to check what kernel is reading from user space. if (__put_user((elf_addr_t)p, argv++)) return -EFAULT; len = strnlen_user((void __user *)p, MAX_ARG_STRLEN); printk(\n Lenght of arg=%ld,%s \n,len,(void __user *)p); if (!len || len MAX_ARG_STRLEN) return -EINVAL; p += len; } when Page size is 16KB o/p is Lenght of arg=6,/init when Page size is 64KB o/p is Lenght of arg=1, so I got null when it read from ELF hum? very strange so essentially it can't read...or to be precise, properly read command arguments (including the executable name itself)? maybe the problem lies somewhere in the initrd/initramfs? -- regards, Mulyadi Santosa Freelance Linux trainer and consultant blog: the-hydra.blogspot.com training: mulyaditraining.blogspot.com ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: page size change on MIPS
On Sat, Feb 5, 2011 at 00:25, David Daney dda...@caviumnetworks.com wrote: Section headers are not relevant to any of this. You need to look at the program headers. Try 'readelf -l' Sorry for jumping in. I think this is the data we needed in this case: readelf --program-headers /bin/ls | grep -A 10 PHDR PHDR 0x34 0x08048034 0x08048034 0x00120 0x00120 R E 0x4 INTERP 0x000154 0x08048154 0x08048154 0x00013 0x00013 R 0x1 [Requesting program interpreter: /lib/ld-linux.so.2] LOAD 0x00 0x08048000 0x08048000 0x17fd8 0x17fd8 R E 0x1000 ...etc If alignment isn't compatible with the expected address or realocation work done by the loader, there comes the crash I guess -- regards, Mulyadi Santosa Freelance Linux trainer and consultant blog: the-hydra.blogspot.com training: mulyaditraining.blogspot.com ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: page size change on MIPS
On 02/03/2011 08:16 PM, naveen yadav wrote: Hi, I am adding readelf info also . mips-linux-gnu-readelf -S squashfs-root/bin/busybox There are 35 section headers, starting at offset 0x174290: Section headers are not relevant to any of this. You need to look at the program headers. Try 'readelf -l' David Daney [...] On Mon, Jan 31, 2011 at 6:38 PM, Ralf Baechler...@linux-mips.org wrote: On Sun, Jan 30, 2011 at 08:32:43PM +0530, Himanshu Aggarwal wrote: Why should the application or the toolchains depend on pagesize? I am not very clear on this. Can someone explain it? To allow loading directly with mmap the executable file's layout must be such that it's it's segments are on offsets that are a multiple of the page size so in turn the linker must know that alignment. Ralf ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: page size change on MIPS
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 dda...@caviumnetworks.com 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 yadavyad.nav...@gmail.com
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 Daneydda...@caviumnetworks.com
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
Re: page size change on MIPS
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. ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: page size change on MIPS
On 01/24/11 10:56, David Daney 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. In principle, one should be able to detect this at run-time, by writing a sequence of values into the PageMask register and seeing which masks 'stick'. /K. ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: page size change on MIPS
On 01/28/2011 01:18 AM, naveen yadav wrote:
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.
Quit trying to change kernel_execve(). It is perfect as it is.
The problem is elsewhere.
Kind regards
Thank you.
On Thu, Jan 27, 2011 at 11:14 PM, David Daneydda...@caviumnetworks.com
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
.setnoreorder \n
li $2, %5 # __NR_execve \n
syscall \n
move%0, $2 \n
move%1, $7\n
.setreorder \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.
Ignore that ^ advice.
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.
Instead look at this issue.
David Daney
On Thu, Jan 27, 2011 at 7:55 PM, naveen yadavyad.nav...@gmail.com
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
.setnoreorder \n
li $2, %5 # __NR_execve \n
syscall \n
move%0, $2 \n
.setreorder \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 Daneydda...@caviumnetworks.com
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
page size change on MIPS
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. 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! 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. ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
