Re: [Crash-utility] [PATCH] add a new command: ipcs
----- Original Message -----
Hello Dave,
I did some effort to change the patch. Now it can support all of the
three facilitis. I also check the kernel from 2.6.18 and up to find the
bugs and fix it. So please refer to the attachment.
--
--
Regards
Qiao Nuohan
Hello Qiao,
First, I don't understand why you dropped the shmid_kernel address
display from the shared memory output? I only requested that you drop
the *inode* address -- because it could be ascertained from the shmid_kernel
structure.
In most crash commands, the relevant "head" data structure address
is displayed, along with a few other key values. The data structure
addresses are important for kernel debugging -- with your output,
statistics are dumped, but if the user actually needed to debug the
IPC facility, there would be no "starting point" kernel virtual address
to work from.
That being the case, the shared memory output should show the
"shmid_kernel" address, the semaphore output should show the
"sem_array" address, and the message queue output should show the
"msg_queue" address. They should be shown in the first column of
each display (similar to the SHMID_KERNEL you showed in your first
patch) and the output restricted to 80 columns.
Secondly, with respect to testing it against my sample set of kernels,
these are the errors that I still see:
(a) On these kernel versions:
2.6.9-89.ELxenU
2.6.15-1.2054_FC5
2.6.16.33-xen
2.6.18-1.2714.el5xen
2.6.18-36.el5xen
2.6.18-58.el5xen
2.6.18-152.el5xen
2.6.31 uniprocessor kernel
the command fails immediatedly with this error:
ipcs: cannot resolve "hugetlbfs_file_operations"
(b) On *all* RHEL5 2.6.18-era kernels, the message queue display
always fails like this:
------ Message Queues --------
KEY MSQID UID PERMS USED-BYTES MESSAGES
ipcs: invalid structure member offset: kern_ipc_perm_id
FILE: ipcs.c LINE: 899 FUNCTION: get_msg_info()
(c) On this 2.6.36-0.16.rc3.git0.fc15 Fedora kernel, it shows:
------ Shared Memory Segments ------
KEY SHMID UID PERMS BYTES NATTCH STATUS
ipcs: invalid kernel virtual address: 10 type: "nsproxy.ipc_ns"
(d) On *all* RHEL4 2.6.9-era and SLES9 2.6.5-era kernels, the command fail like this:
------ Shared Memory Segments ------
KEY SHMID UID PERMS BYTES NATTCH STATUS
ipcs: invalid structure member offset: ipc_id_ary_p
FILE: ipcs.c LINE: 540 FUNCTION: ipc_search_array()
or this:
------ Shared Memory Segments ------
KEY SHMID UID PERMS BYTES NATTCH STATUS
(none allocated)------ Semaphore Arrays --------
KEY SEMID UID PERMS NSEMS
ipcs: invalid structure member offset: ipc_id_ary_p
FILE: ipcs.c LINE: 540 FUNCTION: ipc_search_array()
It would be preferable if you could support all 2.6-era kernels, but if not,
the command should handle them more gracefully by pre-verifying the offsets
before using them, and if they are invalid, then use the option_not_supported()
routine.
Thanks,
Dave