On 3/30/20 10:43 AM, Kees Cook wrote:
...
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 81ff626fc700..e0b8840404a1 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -1457,7 +1457,7 @@
[KNL] Should the hung task detector generate panics.
Format: <integer>
- A nonzero value instructs the kernel to panic when a
+ A value of 1 instructs the kernel to panic when a
hung task is detected. The default value is controlled
by the CONFIG_BOOTPARAM_HUNG_TASK_PANIC build-time
option. The value selected by this boot parameter can
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index 97eb0b552bf8..77b1b844b02b 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -1743,6 +1743,7 @@ struct sysctl_alias {
*/
static const struct sysctl_alias sysctl_aliases[] = {
{"numa_zonelist_order", "vm.numa_zonelist_order" },
Hi Vlastimil,
Maybe best to delete the above line? Because:
a) it was added as an example, and now that you have a real use case in this patch,
the example is no longer required, and
b) numa_zonelist_order is deprecated, as a boot param. Adding support to it in this
brand-new mechanism seems to be going a bit in the opposite direction of deprecation.
And, I don't think you really want all the sysctls to be enabled as boot params, right? Your
comment right above sysctl_aliases[] (shown in patch 2) sort of indicates that only some items
are meant to be both sysctl's and boot params. And that makes sense.
In fact, the sysctl_aliases[] is (or could be) effectively the whitelist that Luis Chamberlain
was requesting in another thread. A whitelist makes good sense, for the reasons Luis listed.
As such, keeping it limited to items that we want, seems like the way to go, IMHO.
thanks,
--
John Hubbard
NVIDIA
+ {"hung_task_panic", "kernel.hung_task_panic" },
{ }
};
diff --git a/kernel/hung_task.c b/kernel/hung_task.c
index 14a625c16cb3..b22b5eeab3cb 100644
--- a/kernel/hung_task.c
+++ b/kernel/hung_task.c
@@ -63,16 +63,6 @@ static struct task_struct *watchdog_task;
unsigned int __read_mostly sysctl_hung_task_panic =
CONFIG_BOOTPARAM_HUNG_TASK_PANIC_VALUE;
-static int __init hung_task_panic_setup(char *str)
-{
- int rc = kstrtouint(str, 0, &sysctl_hung_task_panic);
-
- if (rc)
- return rc;
- return 1;
-}
-__setup("hung_task_panic=", hung_task_panic_setup);
-
static int
hung_task_panic(struct notifier_block *this, unsigned long event, void *ptr)
{
--
2.25.1
