Kernel backup
Hi, I'm working on a project and might do multiple making - I'm afraid if things go wrong. How to keep a backup of the current kernel? Thanks ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Kernel backup
Before even trying to do any development, I think that you need to learn about GRUB (or what bootloader you are using) and how to be able to chose from multiple kernels when booting. On Tue, May 27, 2014 at 7:56 AM, Nada Saif nada.sa...@gmail.com wrote: Hi, I'm working on a project and might do multiple making - I'm afraid if things go wrong. How to keep a backup of the current kernel? Thanks ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Download Linus's latest git tree
Hi All, You can try following steps to checkout to the latest stable kernel. # First clone to the current release. git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git linux-stable cd linux-stable # Create local branch stable git checkout -b stable # Added a remote git tree to the .git/config using following command. git remote add stable git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git # Now fetch the changes to the current stable release. Will checkout the changes to v3.14.y stable. git fetch stable v3.14.y # Now this kernel will merge the changes in to stable branch. git merge FETCH_HEAD Please share your thoughts on this. -Anand Moon On Tuesday, May 27, 2014 7:48 AM, valdis.kletni...@vt.edu valdis.kletni...@vt.edu wrote: On Mon, 26 May 2014 15:04:17 -0300, Lucas Tanure said: git clone --depth 1 git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git Note that '--depth 1' results in a faster initial download, but it has a number of disadvatages - you can't clone it into another tree of yours, nor can you push or pull from it. And most notably, you can't use it for a git bisect. I'd recommend biting the bullet, and doing a full clone (you only have to do that the first time - the next time, even if you need a new copy of the tree, you can clone your original for the basis and not have to refetch it). ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Open and copy a file from the kernel
Hi, I want to process a copy operation from file sent from user space - this copying should be inside the kernel.. I read about using filp_open , will this help me ? Thanks, Nada ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Kernel backup
On 27-05-14 08:56:27, Nada Saif wrote: I'm working on a project and might do multiple making - I'm afraid if things go wrong. How to keep a backup of the current kernel? Just use the packet management of your distribution to build and install new kernels. Under normal circumstances you'd then have several kernels to choose from as the old ones are kept. Your bootmanager also gives you the opportunity to choose from several different kernels and can fall back to older version if something goes wrong. ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Open and copy a file from the kernel
On Tue, 27 May 2014 10:19:37 +0300, Nada Saif said: I want to process a copy operation from file sent from user space - this copying should be inside the kernel.. Why? What problem are you trying to solve by doing this? This is almost certainly a bad design, for a number of reasons. And there's probably a better way to do what you're trying to accomplish. I read about using filp_open , will this help me ? Probably not. pgp7KmA4oUE65.pgp Description: PGP signature ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Open and copy a file from the kernel
how about call_usermodehelper? On Tue, May 27, 2014 at 3:19 PM, Nada Saif nada.sa...@gmail.com wrote: Hi, I want to process a copy operation from file sent from user space - this copying should be inside the kernel.. I read about using filp_open , will this help me ? Thanks, Nada ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Open and copy a file from the kernel
On Tue, May 27, 2014 at 12:49 PM, Nada Saif nada.sa...@gmail.com wrote: Hi, I want to process a copy operation from file sent from user space - this copying should be inside the kernel.. I read about using filp_open , will this help me ? I guess you want to open the files inside kernel and then copy from one to another. That's just not good. If you are trying to learn something like passing data from user space to kernel, you should probably look at sysfs. Very simple wrappers exist that allow you to create a dummy sysfs file(s) where you can have your store and show callbacks do the magic you want to learn. Thanks, Nada ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies -- ---P.K.S ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Download Linus's latest git tree
On Tue, 27 May 2014 00:16:52 -0700, Anand Moon said: Please share your thoughts on this. I'd do it slightly differently, by keeping a master copy of Linus's tree, and a separate tree for the -stable additions (and other separate trees for linux-next or whatever else you feel like...) I keep my git trees under /usr/src - feel free to stick them elsewhere if that makes your workflow or disk management easier. Just remember to fix any pathnames.. :) 1) Get yourself a copy of Linus's tree, almost same as before: cd /usr/src git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git linux Note we called it 'linux', not 'linux-stable'. Remember the full path for this (I keep this one in /usr/src/linux, so that's what I'll use below) Note - this tree should be updated via this. The other trees are different cd /usr/src/linux git pull 2) Make a clone of that tree to use as 'stable': cd /usr/src git clone --local /usr/src/linux linux-stable You now have a copy in /usr/src/linux-stable. Also, *this* clone is local only, so you don't have to re-fetch Linus's tree. git remote add stable git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git git fetch stable git fetch --tags stable This tree you should *NOT* use 'git pull' - use 'git remote update' or 'git fetch v3.specifictag' 3) If you want to get a copy of the linux-next tree as well, it's easy, almost the same workflow: cd /usr/src/ git clode --local /usr/src/linux linux-next git remote add linux-next git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git git fetch linux-next (And again, update via 'git remote update' or 'git fetch') Now the interesting part is that you can do 'git checkout' on all 3 trees *and they're independent* - so you can (for instance) have 3 different 'git bisects' in different stages of completion. Or check out the Linus 3.10 kernel to see how code *used* to be, and the linux-stable 3.14.5 to see how it is *now*, and so on. Or you can check out the Linus v3.15-rc7 or the current linux-next, and see what patches *aren't* in the current linux-stable... or whatever else you feel like doing pgpW8t1D3lCL6.pgp Description: PGP signature ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Download Linus's latest git tree
Hi Validis, Thanks for this new approach. -Anand Moon On Tuesday, May 27, 2014 2:07 PM, valdis.kletni...@vt.edu valdis.kletni...@vt.edu wrote: On Tue, 27 May 2014 00:16:52 -0700, Anand Moon said: Please share your thoughts on this. I'd do it slightly differently, by keeping a master copy of Linus's tree, and a separate tree for the -stable additions (and other separate trees for linux-next or whatever else you feel like...) I keep my git trees under /usr/src - feel free to stick them elsewhere if that makes your workflow or disk management easier. Just remember to fix any pathnames.. :) 1) Get yourself a copy of Linus's tree, almost same as before: cd /usr/src git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git linux Note we called it 'linux', not 'linux-stable'. Remember the full path for this (I keep this one in /usr/src/linux, so that's what I'll use below) Note - this tree should be updated via this. The other trees are different cd /usr/src/linux git pull 2) Make a clone of that tree to use as 'stable': cd /usr/src git clone --local /usr/src/linux linux-stable You now have a copy in /usr/src/linux-stable. Also, *this* clone is local only, so you don't have to re-fetch Linus's tree. git remote add stable git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git git fetch stable git fetch --tags stable This tree you should *NOT* use 'git pull' - use 'git remote update' or 'git fetch v3.specifictag' 3) If you want to get a copy of the linux-next tree as well, it's easy, almost the same workflow: cd /usr/src/ git clode --local /usr/src/linux linux-next git remote add linux-next git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git git fetch linux-next (And again, update via 'git remote update' or 'git fetch') Now the interesting part is that you can do 'git checkout' on all 3 trees *and they're independent* - so you can (for instance) have 3 different 'git bisects' in different stages of completion. Or check out the Linus 3.10 kernel to see how code *used* to be, and the linux-stable 3.14.5 to see how it is *now*, and so on. Or you can check out the Linus v3.15-rc7 or the current linux-next, and see what patches *aren't* in the current linux-stable... or whatever else you feel like doing ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Open and copy a file from the kernel
On Tue, May 27, 2014 at 3:05 PM, Nada Saif nada.sa...@gmail.com wrote: Hi Srivastava, Thanks for your answer. I want to make a backup of any opened file.. whenever the file is opened or updated , it's reflected on its backup.. Hmm, not really done this but i guess you need inotify hooks and some sort of user space daemon that hooks those inotify events. I've not done this but i know it shouldn't be too hard. Just search for inotify. What you are trying isn't kernel thing to do, however i guess you are trying to do something sort of snapshot per change of a file. But again since you are not doing this at file system level I won't recommend doing this inside kernel (opening and copying). Just hook the inotify events in the userspace daemon and let it worry about maintaining a separate version for all files changed. But if you do this won't you run out of space so soon, plus the files you'll create will eat up the inodes which really are earlier versions you are maintaining. Probably you should come up with a consolidated layout of versions you are going to save. Maybe what you can do is have diffs of file in a particular custom format which can then all be zipped into a version database you can maintain. Now just think of doing all this inside kernel. See it's a bad idea and you know it!. You can use scripts to simplify everything. The search operations within your database to lookup a particular version, like going from version 3 to version 8 would require applying diffs which you can easily do in script. If you are not doing the above things I said, then my bad. You need to tell some more about project then maybe I can help. Regards On May 27, 2014 11:29 AM, Pranay Srivastava pran...@gmail.com wrote: On Tue, May 27, 2014 at 12:49 PM, Nada Saif nada.sa...@gmail.com wrote: Hi, I want to process a copy operation from file sent from user space - this copying should be inside the kernel.. I read about using filp_open , will this help me ? I guess you want to open the files inside kernel and then copy from one to another. That's just not good. If you are trying to learn something like passing data from user space to kernel, you should probably look at sysfs. Very simple wrappers exist that allow you to create a dummy sysfs file(s) where you can have your store and show callbacks do the magic you want to learn. Thanks, Nada ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies -- ---P.K.S -- ---P.K.S ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: How to trace the send() in client call
Hi Augusto, But there will be other packets also coming from the network like if some one is browsing the net on mozilla. I only want to trace the send() calls that i have used in my code,is that possible? Regards On Tue, May 27, 2014 at 3:49 AM, Augusto Mecking Caringi augustocari...@gmail.com wrote: On Mon, May 26, 2014 at 1:48 PM, Robert Clove cloverob...@gmail.comwrote: Hi All, I need your help. I have written the client server program in which client is sending the packets to the server. I want to trace the send() that is used in the client program actually want to trace the system call the packet traverses . How to trace ? Hi Robert, You can use the strace command line tool. There is an argument to trace only network related syscalls: -e trace=network Trace all the network related system calls. Take a look on the strace manual page for more information. Best regards. -- Augusto Mecking Caringi ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Simple Misc Driver - Problem with string copy to user
Hi!
Goal, when the user do :
# head -1 /dev/miscdrv
The driver prints: Hello World!
Steps:
# Make
# insmod misc.ko
# head -1 /dev/miscdrv
Why my driver doesn't work ?
What is worg with my read operation?
static ssize_t
misc_drv_read(struct file *filp, char __user * buf, size_t count, loff_t *
offp){
int nbytes;
char * string = hello World;
nbytes = copy_to_user(buf, string, 12);
return nbytes;
}
--
Lucas Tanure
Brazil
Makefile
Description: Binary data
#include linux/module.h
#include linux/init.h
#include linux/fs.h
#include linux/device.h
#include linux/miscdevice.h
#include linux/uaccess.h /* copy_(to,from)_user */
#define MYDEV_NAME miscdrv
static ssize_t
misc_drv_read(struct file *filp, char __user * buf, size_t count, loff_t * offp){
int nbytes;
char * string = hello World;
nbytes = copy_to_user(buf, string, 12);
return nbytes;
}
static ssize_t
misc_drv_write(struct file *filp, const char __user * buf, size_t count, loff_t * offp)
{
return 0;
}
static const struct file_operations misc_drv_fops = {
.read = misc_drv_read,
.write = misc_drv_write,
};
static struct miscdevice my_misc_device = {
.minor = MISC_DYNAMIC_MINOR,
.name = MYDEV_NAME,
.fops = misc_drv_fops,
};
static int __init my_init(void){
dev_info(my_misc_device.this_device, Registering Device\n);
if (misc_register(my_misc_device)) {
pr_err(Couldn't register device misc, %d.\n, my_misc_device.minor);
return -EBUSY;
}
return 0;
}
static void __exit my_exit(void)
{
dev_info(my_misc_device.this_device, Unregistering Device\n);
misc_deregister(my_misc_device);
}
module_init(my_init);
module_exit(my_exit);
MODULE_AUTHOR(Lucas Tanure);
MODULE_DESCRIPTION(Test Misc Device);
MODULE_LICENSE(GPL v2);
___
Kernelnewbies mailing list
Kernelnewbies@kernelnewbies.org
http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Simple Misc Driver - Problem with string copy to user
Lucas Tanure tan...@linux.com writes:
What is worg with my read operation?
static ssize_t
misc_drv_read(struct file *filp, char __user * buf, size_t count, loff_t *
offp){
int nbytes;
char * string = hello World;
nbytes = copy_to_user(buf, string, 12);
return nbytes;
}
copy_to_user returns the number of bytes which could *not* be copied.
So it will return 0 on success, making your read return 0.
Bjørn
___
Kernelnewbies mailing list
Kernelnewbies@kernelnewbies.org
http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Simple Misc Driver - Problem with string copy to user
So, My misc_drv_read returns 0, and it's ok. So why the command head didn't
get the string ?
--
Lucas Tanure
+55 (19) 988176559
On Tue, May 27, 2014 at 9:59 AM, Bjørn Mork bj...@mork.no wrote:
Lucas Tanure tan...@linux.com writes:
What is worg with my read operation?
static ssize_t
misc_drv_read(struct file *filp, char __user * buf, size_t count, loff_t
*
offp){
int nbytes;
char * string = hello World;
nbytes = copy_to_user(buf, string, 12);
return nbytes;
}
copy_to_user returns the number of bytes which could *not* be copied.
So it will return 0 on success, making your read return 0.
Bjørn
___
Kernelnewbies mailing list
Kernelnewbies@kernelnewbies.org
http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Simple Misc Driver - Problem with string copy to user
Lucas Tanure tan...@linux.com writes: So, My misc_drv_read returns 0, and it's ok. So why the command head didn't get the string ? You told it that it got a string with length 0. And that's what it printed. Bjørn ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Simple Misc Driver - Problem with string copy to user
Wow, many thanks. So the read operation should return the total number of bytes, not a true/false int. I need to read more about this operations. Thanks -- Lucas Tanure +55 (19) 988176559 On Tue, May 27, 2014 at 10:05 AM, Bjørn Mork bj...@mork.no wrote: Lucas Tanure tan...@linux.com writes: So, My misc_drv_read returns 0, and it's ok. So why the command head didn't get the string ? You told it that it got a string with length 0. And that's what it printed. Bjørn ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Simple Misc Driver - Problem with string copy to user
Hi! On Die, 2014-05-27 at 10:09 -0300, Lucas Tanure wrote: Wow, many thanks. So the read operation should return the total number of bytes, not a true/false int. The syscall here (done by `head`) is read() ... I need to read more about this operations. .. and the drivers .read function is called if the user-space calls read() on the (opened) device. This .read function returns *) 0 with the number of successfully read bytes *) == 0 on end-of-file. *) 0 on errors. And these error codes are found on `man errno` and one just returns them as -E. [ Fullquote deleted ] Kind regards, Bernd ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Download Linus's latest git tree
On Tue, May 27, 2014 at 04:35:13AM -0400, valdis.kletni...@vt.edu wrote: On Tue, 27 May 2014 00:16:52 -0700, Anand Moon said: Please share your thoughts on this. I'd do it slightly differently, by keeping a master copy of Linus's tree, and a separate tree for the -stable additions (and other separate trees for linux-next or whatever else you feel like...) I keep my git trees under /usr/src - feel free to stick them elsewhere if that makes your workflow or disk management easier. Just remember to fix any pathnames.. :) So are you doing this as root? Because you should never do kernel development as root, just put kernel source trees in your home directory somewhere, like under ~/linux/ thanks, greg k-h ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: How to trace the send() in client call
On Tue, May 27, 2014 at 8:31 AM, Robert Clove cloverob...@gmail.com wrote: But there will be other packets also coming from the network like if some one is browsing the net on mozilla. I only want to trace the send() calls that i have used in my code,is that possible? Robert, You must specify the PID of your process (to attach strace to a running process), or run your program through strace. Yon can use grep to filter only the write syscall. Regards. -- Augusto Mecking Caringi ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Download Linus's latest git tree
On Tue, 27 May 2014 07:28:34 -0700, Greg KH said: So are you doing this as root? Because you should never do kernel development as root, just put kernel source trees in your home directory somewhere, like under ~/linux/ No, I'm not doing the builds as root. /usr/src has been fixed to be owned by source:source like God intended. (And yes, that works just fine because any RPMs that yum wants to scribble under that are scribbled as root so the ownership doesn't matter. :) pgpU0fq6yMtAI.pgp Description: PGP signature ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Download Linus's latest git tree
Have you try the git archive instead of git clone? , if you do not need the history this git option rocks On Tue, May 27, 2014 at 11:16 AM, valdis.kletni...@vt.edu wrote: On Tue, 27 May 2014 07:28:34 -0700, Greg KH said: So are you doing this as root? Because you should never do kernel development as root, just put kernel source trees in your home directory somewhere, like under ~/linux/ No, I'm not doing the builds as root. /usr/src has been fixed to be owned by source:source like God intended. (And yes, that works just fine because any RPMs that yum wants to scribble under that are scribbled as root so the ownership doesn't matter. :) ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Download Linus's latest git tree
On Tue, 27 May 2014 11:28:19 -0500, Victor Rodriguez said: Have you try the git archive instead of git clone? , if you do not need the history this git option rocks That has the same problem as 'clone --depth 1' - you can't bisect using the resulting tree. pgplGNsmTr6Xg.pgp Description: PGP signature ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Simple Misc Driver - Problem with string copy to user
I think it is good for you to read LDD3 or google some corresponding
materials at first.
2014-05-27 20:48 GMT+08:00 Lucas Tanure tan...@linux.com:
Hi!
Goal, when the user do :
# head -1 /dev/miscdrv
The driver prints: Hello World!
Steps:
# Make
# insmod misc.ko
# head -1 /dev/miscdrv
Why my driver doesn't work ?
What is worg with my read operation?
static ssize_t
misc_drv_read(struct file *filp, char __user * buf, size_t count, loff_t *
offp){
int nbytes;
char * string = hello World;
nbytes = copy_to_user(buf, string, 12);
return nbytes;
}
--
Lucas Tanure
Brazil
___
Kernelnewbies mailing list
Kernelnewbies@kernelnewbies.org
http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
___
Kernelnewbies mailing list
Kernelnewbies@kernelnewbies.org
http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
