/proc/<PID>/cmdline empty in Redhat AS2.1 (bugzilla #8

Discussion regarding the installation and configuration of Linux distributions.
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Saadi
Lance Naik
Posts: 33
Joined: Thu Mar 06, 2003 11:06 pm
Location: Chicago, Il - USA

/proc/<PID>/cmdline empty in Redhat AS2.1 (bugzilla #8

Post by Saadi »

I need help, folks.

The problem is that /proc/PID/cmdline shows nuthing.nada.zip.zilch!!! it is a kernel issue and I had reported this issue w/ Redhat. they had sent me a patch to fix this (and recompiled the kernel with the patch) that runs fine on most machines, but unable to run on a machine that has software raid configured. well the patch as follows:

--- linux/fs/proc/base.c.BAD Tue May 6 16:07:12 2003
+++ linux/fs/proc/base.c Tue May 6 16:09:16 2003
@@ -155,6 +155,12 @@
if (len > PAGE_SIZE)
len = PAGE_SIZE;
res = access_process_vm(task, mm->arg_start, buffer, len, 0);
+ /*
+ * If the length is > 4Kb we need to add a 0 to the end
+ */
+ if ((len == PAGE_SIZE) && (res > 0))
+ buffer[res-1] = '\0';
+
// If the nul at the end of args has been overwritten, then
// assume application is using setproctitle(3).
if ( res > 0 && buffer[res-1] != '\0' )

After applying the patch and rebuilding the kernel, it allows processes to pass upto 4KB long arguments.

The kernel I am using is 2.4.9-e.25smp with SMP, RAID and Blcok Device options enabled in "menuconfig". It still does not like the / mount and barks about /dev/md4 which is a mounted filsystem with software raid on.

Can anyone out there compile this patch with the above kernel and make an .rpm file and upload it here. I would really appreciate it, because I have given it up after trying over and over.

Thanks!
Aziz Khawaja
Chicago, Il.
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