diff options
| author | Juergen Gross <jgross@suse.com> | 2021-11-02 10:19:44 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-11-18 14:03:49 +0100 |
| commit | af7d25d7853c286126e660e59cfa52c026334881 (patch) | |
| tree | 4652c38b1690a58590f64ffcc02e90e3ec17c8c7 /Documentation | |
| parent | 96e7880a432a429994f3389ecf90587a4a130a13 (diff) | |
xen/balloon: add late_initcall_sync() for initial ballooning done
commit 40fdea0284bb20814399da0484a658a96c735d90 upstream.
When running as PVH or HVM guest with actual memory < max memory the
hypervisor is using "populate on demand" in order to allow the guest
to balloon down from its maximum memory size. For this to work
correctly the guest must not touch more memory pages than its target
memory size as otherwise the PoD cache will be exhausted and the guest
is crashed as a result of that.
In extreme cases ballooning down might not be finished today before
the init process is started, which can consume lots of memory.
In order to avoid random boot crashes in such cases, add a late init
call to wait for ballooning down having finished for PVH/HVM guests.
Warn on console if initial ballooning fails, panic() after stalling
for more than 3 minutes per default. Add a module parameter for
changing this timeout.
[boris: replaced pr_info() with pr_notice()]
Cc: <stable@vger.kernel.org>
Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20211102091944.17487-1-jgross@suse.com
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index f103667d3727..516499f9ccae 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -5988,6 +5988,13 @@ improve timer resolution at the expense of processing more timer interrupts. + xen.balloon_boot_timeout= [XEN] + The time (in seconds) to wait before giving up to boot + in case initial ballooning fails to free enough memory. + Applies only when running as HVM or PVH guest and + started with less memory configured than allowed at + max. Default is 180. + xen.event_eoi_delay= [XEN] How long to delay EOI handling in case of event storms (jiffies). Default is 10. |