Running 100 applications in background writing and reading on Device… working absolutely fine.
Pre-requisites In order to develop Linux device drivers, it is necessary to have an understanding of the following: C programming. Some in-depth knowledge of C programming is needed, like pointer usage, bit manipulating functions, etc. Microprocessor programming. It is necessary … Continue reading
Hi, I was working on my Driver and got this Error for a function. I checked out other blogs on Internet and it was written that it occurs when you are calling a function before declaring it. But I did … Continue reading
In my lkm,when i printed the value of “HZ”. It comes out 1000. But the actual value defined in the header #include<asm/param.h> is 100. why..?
How we can access our sucll_dev structure of specific device by a proc file system or in its function like read proc ()……….??????/
In the ioctl function at driver level…….., the switch(cmd) statement have ‘cmd’ as the argument but we can see cmd is of ‘unsigned int’ type… i want to ask how the switch function perform case matching…. switch(cmd) { case IOSQSET: … Continue reading
sir i have completed llseek,semaphor & read write with multiple quantums……..
Is there any function to reallocate memory at the kernel level in spite of kmalloc……????
If container of function returns scull_dev pointer, then where the major and minor numbers are located into the different structures??????
Completed: open, close, read (single quantum, multiple quantum),write(single quantum, multiple quantum),semaphore(syn tech). Working: Completion, IOCTL,LSEEK
I have used printk statement in char device driver code. “make” have no warning or error on doing insmod no error is given . but on dmesg the printk statement are not showing. i have checked in /var/log/message but printk … Continue reading
Could any body try ,to satisfied me ,by telling me the truth of the container of function?
why kernel can not dereference user space buffer ??????
at time of the writing in multiple quantum there is killed in kernel page and err reported is sleeping function called from invalid context at arch/x86/mm/fault.c what dose it mean? and kernel crash after 5 min.
while MAKE there is no error. when i try to insmod : following error is produced : insmod : error inserting ‘./modules/lkm.ko’ : -1 operation not permitted But the amazing thing is that my driver is registered in /proc/devices(major number … Continue reading