Re: A basic device driver problem!

John Huntington schrieb:
Dear all,
I compiled a single device driver, but there's some problem like this:

$gcc -O2 -DMODULE -D__KERNEL__ -I/usr/src/linux-2.4.20-8/include -c CharDriver.c
CharDriver.c:22: warning: initialization from incompatible pointer type
CharDriver.c: In function `device_read':
CharDriver.c:50: `VERIFY_WRITE' undeclared (first use in this function)
CharDriver.c:50: (Each undeclared identifier is reported only once
CharDriver.c:50: for each function it appears in.)
make: *** [CharDriver.O] Error 1

My linux kernel version is 2.4.20, it seems 'VERIFY_WRITE' not exist, how can I solve this problem? thank you!



cd <kernel_src>
grep -r VERIFY_WRITE * | grep define:
[...]
include/asm/uaccess.h:#define VERIFY_WRITE 1
[...]

So, look at your source (CharDriver.c) if
there is an

#include <asm/uaccess.h>

at the beginning.

Most likely your link
/usr/include/asm
is missing. It should point to
/usr/src/linux/include/asm-i386/
or whatever your architecture is.

A real dirty solution would be to put an

#define VERIFY_WRITE 1

at the beginning of CharDriver.c.

HTH Martin
.

Relevant Pages