RE: FC3 module sys_print how...
Dear Richard,
I have tried your module to print message to the file in the kernel
level.
I am able to get it work till the initialization level. Later when I
insert the card the system hangs.
Please suggest me what could be the problem. Or is there a way to get
all my LOG messages perfectly even when the system hangs after the
reboot.
Waiting for ur suggestions.
Regards,
Mukund Jampala
>-Original Message-
>From: Richard B. Johnson [mailto:[EMAIL PROTECTED]
>Sent: Friday, July 15, 2005 11:18 PM
>To: Mukund JB.
>Cc: Linux kernel
>Subject: Re: FC3 module sys_print how...
>
>
>Third try...
>
>On Fri, 15 Jul 2005, Richard B. Johnson wrote:
>
>>
>> Second try.
>>
>> On Fri, 15 Jul 2005, Richard B. Johnson wrote:
>>
>>>
>>> It's no longer exported. You can either modify your kernel to
>>> export it or you can use that attached work-around to extract
>>> the symbol offset from /boot/System.map.
>>>
>>> Please note that manipulating files from within a module has
>>> never been supported. It just "sort of" works sometimes. In
>>> your demo code, it will work because the process-context that
>>> obtains the file-handle is the process that is running 'insmod'.
>>> If somebody else tried to write to that file after the module
>>> was installed, all bets are off. I strongly suggest that
>>> you provide hooks in your module (ioctl() or mmap(), etc) that
>>> a user-mode helper program can use to send or receive file-data
>>> from your module.
>>>
>>>
>>> On Fri, 15 Jul 2005, Mukund JB. wrote:
>>>>
>>>>
>>>> Dear Linux-lovers.
>>>>
>>>>
>>>>
>>>> I am trying to build a 2.6.10 linux kernel module to print messages
to
>a
>>>> file. I have done this 2.4 and I was successful but I am failing
here.
>>>>
>>>>
>>>>
>>>> I am using the sys_open, sys_write calls to do so.
>>>>
>>>> I am getting a compilation warning and I find no .ko file created
>>>> finally instead I find an .o.ko file.
>>>>
>>>>
>>>>
>>>> *** WARNIG: "sys_write" [/home/cf.o.ko] undefined!
>>>>
>>>> Below is the module code. Please suggest me what could be the
problem:-
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> #include
>>>>
>>>> #include
>>>>
>>>> #include
>>>>
>>>> #include /* for O_WRONLY */
>>>>
>>>> #include/* for sys_ functions */
>>>>
>>>> #include /* for set_fs(), get_fs() etc. */
>>>>
>>>> #include /* for string length */
>>>>
>>>> #include/* for kmalloc */
>>>>
>>>>
>>>>
>>>> MODULE_LICENSE("GPL");
>>>>
>>>> /*
>>>>
>>>> #define DBG
>>>>
>>>> #define PRINTK(fmt,arg...) printk("DBG INFO <%s> | "
>>>> fmt,__FUNCTION__,##arg)
>>>>
>>>> #else
>>>>
>>>> #define PRINTK(fmt,arg...) while(0)
>>>>
>>>> #endif
>>>>
>>>> */
>>>>
>>>>
>>>>
>>>> typedef struct tagWRITE_TEST
>>>>
>>>> {
>>>>
>>>> unsigned long fd;
>>>>
>>>> unsigned long x;
>>>>
>>>>
>>>>
>>>> }WRITE_TEST, *PWRITE_TEST;
>>>>
>>>>
>>>>
>>>> PWRITE_TEST ptest;
>>>>
>>>>
>>>>
>>>> void SysPrint(char * pString, ...)
>>>>
>>>> {
>>>>
>>>> static char buff[1024];
>>>>
>>>> va_list ap;
>>>>
>>>>
>>>>
>>>> va_start(ap,pString);
>>>>
>>>> vsprintf((char *)buff, pString, ap);
>>>>
>>>> va_end(ap);
>>>>
>>>>
>>>>
>>>> sys_write(ptest->fd,(char *)buff,(size_t)strlen(buff));
>>>>
>>>> }
>>>>
>>>>
>>>>
>>>> int init_module(void)
>>>>
>>>> {
>>>>
>>>>
>>>>
>>>> printk("<%s> invoked!\n",__FUNCTION__);
>>>&g
RE: FC3 module sys_print how...
Dear Richard,
I have tried your module to print message to the file in the kernel
level.
I am able to get it work till the initialization level. Later when I
insert the card the system hangs.
Please suggest me what could be the problem. Or is there a way to get
all my LOG messages perfectly even when the system hangs after the
reboot.
Waiting for ur suggestions.
Regards,
Mukund Jampala
-Original Message-
From: Richard B. Johnson [mailto:[EMAIL PROTECTED]
Sent: Friday, July 15, 2005 11:18 PM
To: Mukund JB.
Cc: Linux kernel
Subject: Re: FC3 module sys_print how...
Third try...
On Fri, 15 Jul 2005, Richard B. Johnson wrote:
Second try.
On Fri, 15 Jul 2005, Richard B. Johnson wrote:
It's no longer exported. You can either modify your kernel to
export it or you can use that attached work-around to extract
the symbol offset from /boot/System.map.
Please note that manipulating files from within a module has
never been supported. It just sort of works sometimes. In
your demo code, it will work because the process-context that
obtains the file-handle is the process that is running 'insmod'.
If somebody else tried to write to that file after the module
was installed, all bets are off. I strongly suggest that
you provide hooks in your module (ioctl() or mmap(), etc) that
a user-mode helper program can use to send or receive file-data
from your module.
On Fri, 15 Jul 2005, Mukund JB. wrote:
Dear Linux-lovers.
I am trying to build a 2.6.10 linux kernel module to print messages
to
a
file. I have done this 2.4 and I was successful but I am failing
here.
I am using the sys_open, sys_write calls to do so.
I am getting a compilation warning and I find no .ko file created
finally instead I find an .o.ko file.
*** WARNIG: sys_write [/home/cf.o.ko] undefined!
Below is the module code. Please suggest me what could be the
problem:-
#include linux/kernel.h
#include linux/module.h
#include linux/moduleparam.h
#include asm/fcntl.h/* for O_WRONLY */
#include linux/syscalls.h /* for sys_ functions */
#include asm/uaccess.h /* for set_fs(), get_fs() etc. */
#include linux/string.h /* for string length */
#include linux/slab.h /* for kmalloc */
MODULE_LICENSE(GPL);
/*
#define DBG
#define PRINTK(fmt,arg...) printk(DBG INFO %s |
fmt,__FUNCTION__,##arg)
#else
#define PRINTK(fmt,arg...) while(0)
#endif
*/
typedef struct tagWRITE_TEST
{
unsigned long fd;
unsigned long x;
}WRITE_TEST, *PWRITE_TEST;
PWRITE_TEST ptest;
void SysPrint(char * pString, ...)
{
static char buff[1024];
va_list ap;
va_start(ap,pString);
vsprintf((char *)buff, pString, ap);
va_end(ap);
sys_write(ptest-fd,(char *)buff,(size_t)strlen(buff));
}
int init_module(void)
{
printk(%s invoked!\n,__FUNCTION__);
printk(File Creation Testing in Kernel Module!\n);
set_fs(get_ds());
/* allocate the memory for structre */
ptest = (PWRITE_TEST)kmalloc(sizeof(WRITE_TEST),GFP_KERNEL);
if(ptest == NULL)
{
printk(Structure Memory Allocation Fails!\n);
return -ENOMEM;
}
ptest-fd = sys_open(srcdebug.txt, O_CREAT | O_WRONLY, 644);
if (ptest-fd == 0)
{
SysPrint(File Creation Error!!!\n);
return 1;
}
SysPrint(File Creation Testing in Kernel Module!\n);
SysPrint(Srinivas Testing the File Creation\n);
sys_close(ptest-fd);
return 0;
}
void cleanup_module(void)
{
printk(Good bye!\n);
/* free the allocated memory */
kfree(ptest);
}
Regards,
Mukund jampala
-
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Cheers,
Dick Johnson
Penguin : Linux version 2.6.12 on an i686 machine (5537.79
BogoMips).
Notice : All mail here is now cached for review by Dictator Bush.
98.36% of all statistics are fiction.
Cheers,
Dick Johnson
Penguin : Linux version 2.6.12 on an i686 machine (5537.79 BogoMips).
Notice : All mail here is now cached for review by Dictator Bush.
98.36% of all statistics are fiction.
Cheers,
Dick Johnson
Penguin : Linux version 2.6.12 on an i686 machine (5537.79 BogoMips).
Notice : All mail here is now cached for review by Dictator Bush.
98.36% of all statistics are fiction.
-
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to [EMAIL PROTECTED]
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Please read the FAQ at http://www.tux.org/lkml/
RE: FC3 module sys_print how...
Dear Richard,
Thanks for the copy.
I will try it now.
I know we should not try to open, Read, write files from the kernel
module.
We have problem with our flash media driver hanging at certain
instances.
And when it hangs you know I can't see the /var/log/messages.
After the reboot, I do NOT find the complete set of messages in
/var/log/messages.
When debug messages are exceeding the limits, is there a better solution
than writing to the file.
Regards,
Mukund Jampala
>-Original Message-
>From: Richard B. Johnson [mailto:[EMAIL PROTECTED]
>Sent: Friday, July 15, 2005 6:19 PM
>To: Mukund JB.
>Cc: Linux kernel
>Subject: Re: FC3 module sys_print how...
>
>
>It's no longer exported. You can either modify your kernel to
>export it or you can use that attached work-around to extract
>the symbol offset from /boot/System.map.
>
>Please note that manipulating files from within a module has
>never been supported. It just "sort of" works sometimes. In
>your demo code, it will work because the process-context that
>obtains the file-handle is the process that is running 'insmod'.
>If somebody else tried to write to that file after the module
>was installed, all bets are off. I strongly suggest that
>you provide hooks in your module (ioctl() or mmap(), etc) that
>a user-mode helper program can use to send or receive file-data
>from your module.
>
>
>On Fri, 15 Jul 2005, Mukund JB. wrote:
>>
>>
>> Dear Linux-lovers.
>>
>>
>>
>> I am trying to build a 2.6.10 linux kernel module to print messages
to a
>> file. I have done this 2.4 and I was successful but I am failing
here.
>>
>>
>>
>> I am using the sys_open, sys_write calls to do so.
>>
>> I am getting a compilation warning and I find no .ko file created
>> finally instead I find an .o.ko file.
>>
>>
>>
>> *** WARNIG: "sys_write" [/home/cf.o.ko] undefined!
>>
>> Below is the module code. Please suggest me what could be the
problem:-
>>
>>
>>
>>
>>
>> #include
>>
>> #include
>>
>> #include
>>
>> #include /* for O_WRONLY */
>>
>> #include/* for sys_ functions */
>>
>> #include /* for set_fs(), get_fs() etc. */
>>
>> #include /* for string length */
>>
>> #include/* for kmalloc */
>>
>>
>>
>> MODULE_LICENSE("GPL");
>>
>> /*
>>
>> #define DBG
>>
>> #define PRINTK(fmt,arg...) printk("DBG INFO <%s> | "
>> fmt,__FUNCTION__,##arg)
>>
>> #else
>>
>> #define PRINTK(fmt,arg...) while(0)
>>
>> #endif
>>
>> */
>>
>>
>>
>> typedef struct tagWRITE_TEST
>>
>> {
>>
>> unsigned long fd;
>>
>> unsigned long x;
>>
>>
>>
>> }WRITE_TEST, *PWRITE_TEST;
>>
>>
>>
>> PWRITE_TEST ptest;
>>
>>
>>
>> void SysPrint(char * pString, ...)
>>
>> {
>>
>> static char buff[1024];
>>
>> va_list ap;
>>
>>
>>
>> va_start(ap,pString);
>>
>> vsprintf((char *)buff, pString, ap);
>>
>> va_end(ap);
>>
>>
>>
>> sys_write(ptest->fd,(char *)buff,(size_t)strlen(buff));
>>
>> }
>>
>>
>>
>> int init_module(void)
>>
>> {
>>
>>
>>
>> printk("<%s> invoked!\n",__FUNCTION__);
>>
>> printk("File Creation Testing in Kernel Module!\n");
>>
>>
>>
>> set_fs(get_ds());
>>
>>
>>
>> /* allocate the memory for structre */
>>
>> ptest = (PWRITE_TEST)kmalloc(sizeof(WRITE_TEST),GFP_KERNEL);
>>
>> if(ptest == NULL)
>>
>> {
>>
>>printk("Structure Memory Allocation Fails!\n");
>>
>>return -ENOMEM;
>>
>> }
>>
>>
>>
>> ptest->fd = sys_open("srcdebug.txt", O_CREAT | O_WRONLY, 644);
>>
>> if (ptest->fd == 0)
>>
>> {
>>
>>SysPrint("File Creation Error!!!\n");
>>
>>return 1;
>>
>> }
>>
>>
>>
>> SysPrint("File Creation Testing in Kernel Module!\n");
>>
>> SysPrint("Srinivas Testing the File Creation\n");
>>
>> sys_close(ptest->fd);
>>
>>
>>
>> return 0;
>>
>> }
>>
>>
>>
>> void cleanup_module(void)
>>
>> {
>>
>> printk("Good bye!\n");
>>
>>
>>
>> /* free the allocated memory */
>>
>> kfree(ptest);
>>
>> }
>>
>>
>>
>> Regards,
>>
>> Mukund jampala
>>
>>
>>
>>
>> -
>> To unsubscribe from this list: send the line "unsubscribe
linux-kernel"
>in
>> the body of a message to [EMAIL PROTECTED]
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at http://www.tux.org/lkml/
>>
>
>Cheers,
>Dick Johnson
>Penguin : Linux version 2.6.12 on an i686 machine (5537.79 BogoMips).
> Notice : All mail here is now cached for review by Dictator Bush.
> 98.36% of all statistics are fiction.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
RE: FC3 module sys_print how...
Dear Richard,
Thanks for the copy.
I will try it now.
I know we should not try to open, Read, write files from the kernel
module.
We have problem with our flash media driver hanging at certain
instances.
And when it hangs you know I can't see the /var/log/messages.
After the reboot, I do NOT find the complete set of messages in
/var/log/messages.
When debug messages are exceeding the limits, is there a better solution
than writing to the file.
Regards,
Mukund Jampala
-Original Message-
From: Richard B. Johnson [mailto:[EMAIL PROTECTED]
Sent: Friday, July 15, 2005 6:19 PM
To: Mukund JB.
Cc: Linux kernel
Subject: Re: FC3 module sys_print how...
It's no longer exported. You can either modify your kernel to
export it or you can use that attached work-around to extract
the symbol offset from /boot/System.map.
Please note that manipulating files from within a module has
never been supported. It just sort of works sometimes. In
your demo code, it will work because the process-context that
obtains the file-handle is the process that is running 'insmod'.
If somebody else tried to write to that file after the module
was installed, all bets are off. I strongly suggest that
you provide hooks in your module (ioctl() or mmap(), etc) that
a user-mode helper program can use to send or receive file-data
from your module.
On Fri, 15 Jul 2005, Mukund JB. wrote:
Dear Linux-lovers.
I am trying to build a 2.6.10 linux kernel module to print messages
to a
file. I have done this 2.4 and I was successful but I am failing
here.
I am using the sys_open, sys_write calls to do so.
I am getting a compilation warning and I find no .ko file created
finally instead I find an .o.ko file.
*** WARNIG: sys_write [/home/cf.o.ko] undefined!
Below is the module code. Please suggest me what could be the
problem:-
#include linux/kernel.h
#include linux/module.h
#include linux/moduleparam.h
#include asm/fcntl.h/* for O_WRONLY */
#include linux/syscalls.h /* for sys_ functions */
#include asm/uaccess.h /* for set_fs(), get_fs() etc. */
#include linux/string.h /* for string length */
#include linux/slab.h /* for kmalloc */
MODULE_LICENSE(GPL);
/*
#define DBG
#define PRINTK(fmt,arg...) printk(DBG INFO %s |
fmt,__FUNCTION__,##arg)
#else
#define PRINTK(fmt,arg...) while(0)
#endif
*/
typedef struct tagWRITE_TEST
{
unsigned long fd;
unsigned long x;
}WRITE_TEST, *PWRITE_TEST;
PWRITE_TEST ptest;
void SysPrint(char * pString, ...)
{
static char buff[1024];
va_list ap;
va_start(ap,pString);
vsprintf((char *)buff, pString, ap);
va_end(ap);
sys_write(ptest-fd,(char *)buff,(size_t)strlen(buff));
}
int init_module(void)
{
printk(%s invoked!\n,__FUNCTION__);
printk(File Creation Testing in Kernel Module!\n);
set_fs(get_ds());
/* allocate the memory for structre */
ptest = (PWRITE_TEST)kmalloc(sizeof(WRITE_TEST),GFP_KERNEL);
if(ptest == NULL)
{
printk(Structure Memory Allocation Fails!\n);
return -ENOMEM;
}
ptest-fd = sys_open(srcdebug.txt, O_CREAT | O_WRONLY, 644);
if (ptest-fd == 0)
{
SysPrint(File Creation Error!!!\n);
return 1;
}
SysPrint(File Creation Testing in Kernel Module!\n);
SysPrint(Srinivas Testing the File Creation\n);
sys_close(ptest-fd);
return 0;
}
void cleanup_module(void)
{
printk(Good bye!\n);
/* free the allocated memory */
kfree(ptest);
}
Regards,
Mukund jampala
-
To unsubscribe from this list: send the line unsubscribe
linux-kernel
in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Cheers,
Dick Johnson
Penguin : Linux version 2.6.12 on an i686 machine (5537.79 BogoMips).
Notice : All mail here is now cached for review by Dictator Bush.
98.36% of all statistics are fiction.
-
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
