Re: [Crash-utility] [PATCH] add a new command: ipcs
----- Original Message -----
Hello Dave,
I cannot get all kernels at hand. So I have to ask you about the code.
Please show me.
Why not? Just download the upstream kernels from here:
http://www.kernel.org/pub/linux/kernel/v2.6/
>
> (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()
I want to see the struct msg_queue and struct struct kern_ipc_perm.
Here is the output from a RHEL5 kernel:
crash> msg_queue
struct msg_queue {
struct kern_ipc_perm q_perm;
int q_id;
time_t q_stime;
time_t q_rtime;
time_t q_ctime;
long unsigned int q_cbytes;
long unsigned int q_qnum;
long unsigned int q_qbytes;
pid_t q_lspid;
pid_t q_lrpid;
struct list_head q_messages;
struct list_head q_receivers;
struct list_head q_senders;
}
SIZE: 160
crash> kern_ipc_perm
struct kern_ipc_perm {
spinlock_t lock;
int deleted;
key_t key;
uid_t uid;
gid_t gid;
uid_t cuid;
gid_t cgid;
mode_t mode;
long unsigned int seq;
void *security;
}
SIZE: 48
crash>
which is the same as the upstream 2.6.18 kernel.
>
> (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"
what is struct nsproxy? Or is there any symbol referring to ipc_ns?
crash> nsproxy
struct nsproxy {
atomic_t count;
struct uts_namespace *uts_ns;
struct ipc_namespace *ipc_ns;
struct mnt_namespace *mnt_ns;
struct pid_namespace *pid_ns;
struct net *net_ns;
}
SIZE: 48
crash>
It's the same as upstream 2.6.36, but it's not the offset that's invalid,
it's the NULL "nsproxy" address.
>
>
> (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()
>
what is struct ipc_id? And what is entries in struct ipc_id or something
similar to it?
This is from a RHEL4 kernel -- and the upstream 2.6.9 kernel is the same:
crash> ipc_id
struct ipc_id {
struct kern_ipc_perm *p;
}
SIZE: 8
crash> kern_ipc_perm
struct kern_ipc_perm {
spinlock_t lock;
int deleted;
key_t key;
uid_t uid;
gid_t gid;
uid_t cuid;
gid_t cgid;
mode_t mode;
long unsigned int seq;
void *security;
}
SIZE: 56
crash>
Dave