nsm_use_hostnames is a module parameter and it will be exported to sysctl
procfs. This is to let user sometimes change it from userspace. But the
minimal unit for sysctl procfs read/write it sizeof(int).
In big endian system, the converting from/to bool to/from int will cause
error for proc items.
This patch changes the type definition of nsm_use_hostnames.
The test case I used:
/***************************************************************/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/sysctl.h>
bool __read_mostly nsm_use_hostnames;
module_param(nsm_use_hostnames, bool, 0644);
static struct ctl_table my_sysctl[] = {
{
.procname = "nsm_use_hostnames",
.data = &nsm_use_hostnames,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{}
};
static struct ctl_table my_root[] = {
{
.procname = "mysysctl",
.mode = 0555,
.child = my_sysctl,
},
{}
};
static struct ctl_table_header * my_ctl_header;
static int __init sysctl_exam_init(void)
{
my_ctl_header = register_sysctl_table(&my_root);
if (my_ctl_header == NULL)
printk("error regiester sysctl");
return 0;
}
static void __exit sysctl_exam_exit(void)
{
unregister_sysctl_table(my_ctl_header);
}
module_init(sysctl_exam_init);
module_exit(sysctl_exam_exit);
MODULE_LICENSE("GPL");
/****************************************************************/
[root@bigendian my]# insmod -f /root/my/hello.ko nsm_use_hostnames=1
[root@bigendian my]# cat /proc/sys/mysysctl/nsm_use_hostnames
16777216
After I change the bool to int:
[root@bigendian my]# insmod -f /root/my/hello.ko nsm_use_hostnames=1
[root@bigendian my]# cat /proc/sys/mysysctl/nsm_use_hostnames
1
In little endian system, there is no such issue.
Jia He (1):
lockd: Change nsm_use_hostnames from bool to u32
fs/lockd/mon.c | 2 +-
fs/lockd/svc.c | 2 +-
include/linux/lockd/lockd.h | 2 +-
3 files changed, 3 insertions(+), 3 deletions(-)
--
2.5.5
nsm_use_hostnames is a module paramter and it will be exported to sysctl
procfs. This is to let user sometimes change it from userspace. But the
minimal unit for sysctl procfs read/write it sizeof(int).
In big endian system, the converting from/to bool to/from int will cause
error for proc items.
This patch changes the type definition of nsm_use_hostnames.
V2: Changes extern type in lockd.h
Signed-off-by: Jia He <[email protected]>
---
fs/lockd/mon.c | 2 +-
fs/lockd/svc.c | 2 +-
include/linux/lockd/lockd.h | 2 +-
3 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/fs/lockd/mon.c b/fs/lockd/mon.c
index 19166d4..3e7ff4d 100644
--- a/fs/lockd/mon.c
+++ b/fs/lockd/mon.c
@@ -57,7 +57,7 @@ static DEFINE_SPINLOCK(nsm_lock);
* Local NSM state
*/
u32 __read_mostly nsm_local_state;
-bool __read_mostly nsm_use_hostnames;
+u32 __read_mostly nsm_use_hostnames;
static inline struct sockaddr *nsm_addr(const struct nsm_handle *nsm)
{
diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c
index fc4084e..308033d 100644
--- a/fs/lockd/svc.c
+++ b/fs/lockd/svc.c
@@ -658,7 +658,7 @@ module_param_call(nlm_udpport, param_set_port, param_get_int,
&nlm_udpport, 0644);
module_param_call(nlm_tcpport, param_set_port, param_get_int,
&nlm_tcpport, 0644);
-module_param(nsm_use_hostnames, bool, 0644);
+module_param(nsm_use_hostnames, u32, 0644);
module_param(nlm_max_connections, uint, 0644);
static int lockd_init_net(struct net *net)
diff --git a/include/linux/lockd/lockd.h b/include/linux/lockd/lockd.h
index c153738..db52152 100644
--- a/include/linux/lockd/lockd.h
+++ b/include/linux/lockd/lockd.h
@@ -196,7 +196,7 @@ extern struct svc_procedure nlmsvc_procedures4[];
#endif
extern int nlmsvc_grace_period;
extern unsigned long nlmsvc_timeout;
-extern bool nsm_use_hostnames;
+extern u32 nsm_use_hostnames;
extern u32 nsm_local_state;
/*
--
2.5.5
hi, jia
nice catch!
However I think we should fix it totally.
This is because do_proc_dointvec_conv() try to get a int value from a bool *.
something like below might help. pls. ignore the code style and this is tested :)
diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c
index fc4084e..7eeaee4 100644
--- a/fs/lockd/svc.c
+++ b/fs/lockd/svc.c
@@ -519,6 +519,8 @@ EXPORT_SYMBOL_GPL(lockd_down);
* Sysctl parameters (same as module parameters, different interface).
*/
+int proc_dou8vec(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos);
static struct ctl_table nlm_sysctls[] = {
{
.procname = "nlm_grace_period",
@@ -561,7 +563,7 @@ static struct ctl_table nlm_sysctls[] = {
.data = &nsm_use_hostnames,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = proc_dou8vec,
},
{
.procname = "nsm_local_state",
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 706309f..6307737 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -2112,6 +2112,30 @@ static int proc_put_char(void __user **buf, size_t *size, char c)
return 0;
}
+
+static int do_proc_dou8vec_conv(bool *negp, unsigned long *lvalp,
+ u8 *valp,
+ int write, void *data)
+{
+ if (write) {
+ if (*negp) {
+ *valp = -*lvalp;
+ } else {
+ *valp = *lvalp;
+ }
+ } else {
+ int val = *valp;
+ if (val < 0) {
+ *negp = true;
+ *lvalp = -(unsigned long)val;
+ } else {
+ *negp = false;
+ *lvalp = (unsigned long)val;
+ }
+ }
+ return 0;
+}
+
static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
int *valp,
int write, void *data)
@@ -2296,6 +2320,14 @@ int proc_douintvec(struct ctl_table *table, int write,
do_proc_douintvec_conv, NULL);
}
+int proc_dou8vec(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ return do_proc_dointvec(table, write, buffer, lenp, ppos,
+ do_proc_dou8vec_conv, NULL);
+}
+
+
在 2016/12/11 23:36, Jia He 写道:
> nsm_use_hostnames is a module paramter and it will be exported to sysctl
> procfs. This is to let user sometimes change it from userspace. But the
> minimal unit for sysctl procfs read/write it sizeof(int).
> In big endian system, the converting from/to bool to/from int will cause
> error for proc items.
>
> This patch changes the type definition of nsm_use_hostnames.
>
> V2: Changes extern type in lockd.h
> Signed-off-by: Jia He <[email protected]>
> ---
> fs/lockd/mon.c | 2 +-
> fs/lockd/svc.c | 2 +-
> include/linux/lockd/lockd.h | 2 +-
> 3 files changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/fs/lockd/mon.c b/fs/lockd/mon.c
> index 19166d4..3e7ff4d 100644
> --- a/fs/lockd/mon.c
> +++ b/fs/lockd/mon.c
> @@ -57,7 +57,7 @@ static DEFINE_SPINLOCK(nsm_lock);
> * Local NSM state
> */
> u32 __read_mostly nsm_local_state;
> -bool __read_mostly nsm_use_hostnames;
> +u32 __read_mostly nsm_use_hostnames;
>
> static inline struct sockaddr *nsm_addr(const struct nsm_handle *nsm)
> {
> diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c
> index fc4084e..308033d 100644
> --- a/fs/lockd/svc.c
> +++ b/fs/lockd/svc.c
> @@ -658,7 +658,7 @@ module_param_call(nlm_udpport, param_set_port, param_get_int,
> &nlm_udpport, 0644);
> module_param_call(nlm_tcpport, param_set_port, param_get_int,
> &nlm_tcpport, 0644);
> -module_param(nsm_use_hostnames, bool, 0644);
> +module_param(nsm_use_hostnames, u32, 0644);
> module_param(nlm_max_connections, uint, 0644);
>
> static int lockd_init_net(struct net *net)
> diff --git a/include/linux/lockd/lockd.h b/include/linux/lockd/lockd.h
> index c153738..db52152 100644
> --- a/include/linux/lockd/lockd.h
> +++ b/include/linux/lockd/lockd.h
> @@ -196,7 +196,7 @@ extern struct svc_procedure nlmsvc_procedures4[];
> #endif
> extern int nlmsvc_grace_period;
> extern unsigned long nlmsvc_timeout;
> -extern bool nsm_use_hostnames;
> +extern u32 nsm_use_hostnames;
> extern u32 nsm_local_state;
>
> /*
>
在 2016/12/11 23:36, Jia He 写道:
> nsm_use_hostnames is a module parameter and it will be exported to sysctl
> procfs. This is to let user sometimes change it from userspace. But the
> minimal unit for sysctl procfs read/write it sizeof(int).
> In big endian system, the converting from/to bool to/from int will cause
> error for proc items.
hi, Jia
not only in BE system. :)
Current code is just touching a wrong pointer.
some tests based on yours
u8 __read_mostly nsm_use_hostnames[4]={1,2,3,4}; // an arrary of u8, and [0] passed to ctl_table as data
static struct ctl_table my_sysctl[] = {
{
.procname = "nsm_use_hostnames",
.data = &nsm_use_hostnames[0],//u8,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{}
};
then run your tests and result will be
root@ltcalpine2-lp13:~/linux/bench# cat /proc/sys/mysysctl/nsm_use_hostnames
67305985( This is 0x4030201, expected be 0x1)
So your fix patch work around it. But I suggest we can support u8/u16, not only int/double int.
thanks
xinhui
>
> This patch changes the type definition of nsm_use_hostnames.
>
> The test case I used:
> /***************************************************************/
> #include <linux/kernel.h>
> #include <linux/module.h>
> #include <linux/sysctl.h>
>
> bool __read_mostly nsm_use_hostnames;
> module_param(nsm_use_hostnames, bool, 0644);
>
> static struct ctl_table my_sysctl[] = {
> {
> .procname = "nsm_use_hostnames",
> .data = &nsm_use_hostnames,
> .maxlen = sizeof(int),
> .mode = 0644,
> .proc_handler = &proc_dointvec,
> },
> {}
> };
>
> static struct ctl_table my_root[] = {
> {
> .procname = "mysysctl",
> .mode = 0555,
> .child = my_sysctl,
> },
> {}
> };
>
> static struct ctl_table_header * my_ctl_header;
>
> static int __init sysctl_exam_init(void)
> {
> my_ctl_header = register_sysctl_table(&my_root);
> if (my_ctl_header == NULL)
> printk("error regiester sysctl");
>
> return 0;
> }
>
> static void __exit sysctl_exam_exit(void)
> {
> unregister_sysctl_table(my_ctl_header);
> }
>
> module_init(sysctl_exam_init);
> module_exit(sysctl_exam_exit);
> MODULE_LICENSE("GPL");
> /****************************************************************/
>
> [root@bigendian my]# insmod -f /root/my/hello.ko nsm_use_hostnames=1
> [root@bigendian my]# cat /proc/sys/mysysctl/nsm_use_hostnames
> 16777216
>
> After I change the bool to int:
> [root@bigendian my]# insmod -f /root/my/hello.ko nsm_use_hostnames=1
> [root@bigendian my]# cat /proc/sys/mysysctl/nsm_use_hostnames
> 1
>
> In little endian system, there is no such issue.
>
> Jia He (1):
> lockd: Change nsm_use_hostnames from bool to u32
>
> fs/lockd/mon.c | 2 +-
> fs/lockd/svc.c | 2 +-
> include/linux/lockd/lockd.h | 2 +-
> 3 files changed, 3 insertions(+), 3 deletions(-)
>
在 2016/12/12 01:43, Pan Xinhui 写道:
>
> hi, jia
> nice catch!
> However I think we should fix it totally.
> This is because do_proc_dointvec_conv() try to get a int value from a bool *.
>
> something like below might help. pls. ignore the code style and this is tested :)
_untested_.
Hi Xinhui
Thanks, it really works.
Will send out V3 soon afterwards
B.R.
Jia
On 12/12/16 1:43 AM, Pan Xinhui wrote:
>
> hi, jia
> nice catch!
> However I think we should fix it totally.
> This is because do_proc_dointvec_conv() try to get a int value from a bool *.
>
> something like below might help. pls. ignore the code style and this is tested :)
>
> diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c
> index fc4084e..7eeaee4 100644
> --- a/fs/lockd/svc.c
> +++ b/fs/lockd/svc.c
> @@ -519,6 +519,8 @@ EXPORT_SYMBOL_GPL(lockd_down);
> * Sysctl parameters (same as module parameters, different interface).
> */
>
> +int proc_dou8vec(struct ctl_table *table, int write,
> + void __user *buffer, size_t *lenp, loff_t
> *ppos);
> static struct ctl_table nlm_sysctls[] = {
> {
> .procname = "nlm_grace_period",
> @@ -561,7 +563,7 @@ static struct ctl_table nlm_sysctls[] = {
> .data = &nsm_use_hostnames,
> .maxlen = sizeof(int),
> .mode = 0644,
> - .proc_handler = proc_dointvec,
> + .proc_handler = proc_dou8vec,
> },
> {
> .procname = "nsm_local_state",
> diff --git a/kernel/sysctl.c b/kernel/sysctl.c
> index 706309f..6307737 100644
> --- a/kernel/sysctl.c
> +++ b/kernel/sysctl.c
> @@ -2112,6 +2112,30 @@ static int proc_put_char(void __user **buf, size_t
> *size, char c)
> return 0;
> }
>
> +
> +static int do_proc_dou8vec_conv(bool *negp, unsigned long *lvalp,
> + u8 *valp,
> + int write, void *data)
> +{
> + if (write) {
> + if (*negp) {
> + *valp = -*lvalp;
> + } else {
> + *valp = *lvalp;
> + }
> + } else {
> + int val = *valp;
> + if (val < 0) {
> + *negp = true;
> + *lvalp = -(unsigned long)val;
> + } else {
> + *negp = false;
> + *lvalp = (unsigned long)val;
> + }
> + }
> + return 0;
> +}
> +
> static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
> int *valp,
> int write, void *data)
> @@ -2296,6 +2320,14 @@ int proc_douintvec(struct ctl_table *table, int write,
> do_proc_douintvec_conv, NULL);
> }
>
> +int proc_dou8vec(struct ctl_table *table, int write,
> + void __user *buffer, size_t *lenp, loff_t *ppos)
> +{
> + return do_proc_dointvec(table, write, buffer, lenp, ppos,
> + do_proc_dou8vec_conv, NULL);
> +}
> +
> +
>
> 在 2016/12/11 23:36, Jia He 写道:
>> nsm_use_hostnames is a module paramter and it will be exported to sysctl
>> procfs. This is to let user sometimes change it from userspace. But the
>> minimal unit for sysctl procfs read/write it sizeof(int).
>> In big endian system, the converting from/to bool to/from int will cause
>> error for proc items.
>>
>> This patch changes the type definition of nsm_use_hostnames.
>>
>> V2: Changes extern type in lockd.h
>> Signed-off-by: Jia He <[email protected]>
>> ---
>> fs/lockd/mon.c | 2 +-
>> fs/lockd/svc.c | 2 +-
>> include/linux/lockd/lockd.h | 2 +-
>> 3 files changed, 3 insertions(+), 3 deletions(-)
>>
>> diff --git a/fs/lockd/mon.c b/fs/lockd/mon.c
>> index 19166d4..3e7ff4d 100644
>> --- a/fs/lockd/mon.c
>> +++ b/fs/lockd/mon.c
>> @@ -57,7 +57,7 @@ static DEFINE_SPINLOCK(nsm_lock);
>> * Local NSM state
>> */
>> u32 __read_mostly nsm_local_state;
>> -bool __read_mostly nsm_use_hostnames;
>> +u32 __read_mostly nsm_use_hostnames;
>>
>> static inline struct sockaddr *nsm_addr(const struct nsm_handle *nsm)
>> {
>> diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c
>> index fc4084e..308033d 100644
>> --- a/fs/lockd/svc.c
>> +++ b/fs/lockd/svc.c
>> @@ -658,7 +658,7 @@ module_param_call(nlm_udpport, param_set_port,
>> param_get_int,
>> &nlm_udpport, 0644);
>> module_param_call(nlm_tcpport, param_set_port, param_get_int,
>> &nlm_tcpport, 0644);
>> -module_param(nsm_use_hostnames, bool, 0644);
>> +module_param(nsm_use_hostnames, u32, 0644);
>> module_param(nlm_max_connections, uint, 0644);
>>
>> static int lockd_init_net(struct net *net)
>> diff --git a/include/linux/lockd/lockd.h b/include/linux/lockd/lockd.h
>> index c153738..db52152 100644
>> --- a/include/linux/lockd/lockd.h
>> +++ b/include/linux/lockd/lockd.h
>> @@ -196,7 +196,7 @@ extern struct svc_procedure nlmsvc_procedures4[];
>> #endif
>> extern int nlmsvc_grace_period;
>> extern unsigned long nlmsvc_timeout;
>> -extern bool nsm_use_hostnames;
>> +extern u32 nsm_use_hostnames;
>> extern u32 nsm_local_state;
>>
>> /*
>>
>
>
Hi Jia,
[auto build test ERROR on nfsd/nfsd-next]
[also build test ERROR on v4.9 next-20161209]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Jia-He/lockd-Change-nsm_use_hostnames-from-bool-to-u32/20161212-001614
base: git://linux-nfs.org/~bfields/linux.git nfsd-next
config: x86_64-kexec (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64
All errors (new ones prefixed by >>):
In file included from include/linux/module.h:18:0,
from fs/lockd/svc.c:15:
>> include/linux/moduleparam.h:146:27: error: expected ')' before '&' token
param_check_##type(name, &(value)); \
^
include/linux/moduleparam.h:126:2: note: in expansion of macro 'module_param_named'
module_param_named(name, name, type, perm)
^~~~~~~~~~~~~~~~~~
fs/lockd/svc.c:661:1: note: in expansion of macro 'module_param'
module_param(nsm_use_hostnames, u32, 0644);
^~~~~~~~~~~~
>> include/linux/moduleparam.h:147:25: error: 'param_ops_u32' undeclared here (not in a function)
module_param_cb(name, ¶m_ops_##type, &value, perm); \
^
include/linux/moduleparam.h:224:39: note: in definition of macro '__module_param_call'
= { __param_str_##name, THIS_MODULE, ops, \
^~~
include/linux/moduleparam.h:147:2: note: in expansion of macro 'module_param_cb'
module_param_cb(name, ¶m_ops_##type, &value, perm); \
^~~~~~~~~~~~~~~
include/linux/moduleparam.h:126:2: note: in expansion of macro 'module_param_named'
module_param_named(name, name, type, perm)
^~~~~~~~~~~~~~~~~~
fs/lockd/svc.c:661:1: note: in expansion of macro 'module_param'
module_param(nsm_use_hostnames, u32, 0644);
^~~~~~~~~~~~
vim +146 include/linux/moduleparam.h
546970bc Rusty Russell 2010-08-11 140 *
546970bc Rusty Russell 2010-08-11 141 * Usually it's a good idea to have variable names and user-exposed names the
546970bc Rusty Russell 2010-08-11 142 * same, but that's harder if the variable must be non-static or is inside a
546970bc Rusty Russell 2010-08-11 143 * structure. This allows exposure under a different name.
546970bc Rusty Russell 2010-08-11 144 */
546970bc Rusty Russell 2010-08-11 145 #define module_param_named(name, value, type, perm) \
546970bc Rusty Russell 2010-08-11 @146 param_check_##type(name, &(value)); \
546970bc Rusty Russell 2010-08-11 @147 module_param_cb(name, ¶m_ops_##type, &value, perm); \
546970bc Rusty Russell 2010-08-11 148 __MODULE_PARM_TYPE(name, #type)
546970bc Rusty Russell 2010-08-11 149
546970bc Rusty Russell 2010-08-11 150 /**
:::::: The code at line 146 was first introduced by commit
:::::: 546970bc6afc7fb37447fbac09b82c7884662c21 param: add kerneldoc to moduleparam.h
:::::: TO: Rusty Russell <[email protected]>
:::::: CC: Rusty Russell <[email protected]>
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation