Mailing List Archive

[xen master] pmstat: Limit hypercalls under HWP
commit 052d78fbec6a3163281df1b4204d6d606507c4c8
Author: Jason Andryuk <jandryuk@gmail.com>
AuthorDate: Thu Jan 25 16:11:49 2024 +0100
Commit: Jan Beulich <jbeulich@suse.com>
CommitDate: Thu Jan 25 16:11:49 2024 +0100

pmstat: Limit hypercalls under HWP

When HWP is active, the cpufreq P-state information is not updated. In
that case, return -EOPNOTSUPP instead of bogus, incomplete info.

Similarly, set_cpufreq_para() is not applicable when HWP is active.
Many of the options already checked the governor and were inaccessible,
but SCALING_MIN/MAX_FREQ was still accessible (though it would do
nothing). Add an ealier HWP check to handle all cases.

Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
---
xen/drivers/acpi/pmstat.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/xen/drivers/acpi/pmstat.c b/xen/drivers/acpi/pmstat.c
index 803971bdb0..998d2e3c65 100644
--- a/xen/drivers/acpi/pmstat.c
+++ b/xen/drivers/acpi/pmstat.c
@@ -66,6 +66,8 @@ int do_get_pm_info(struct xen_sysctl_get_pmstat *op)
return -ENODEV;
if ( !cpufreq_driver.init )
return -ENODEV;
+ if ( hwp_active() )
+ return -EOPNOTSUPP;
if ( !pmpt || !(pmpt->perf.init & XEN_PX_INIT) )
return -EINVAL;
break;
@@ -330,6 +332,9 @@ static int set_cpufreq_para(struct xen_sysctl_pm_op *op)
if ( !policy || !policy->governor )
return -EINVAL;

+ if ( hwp_active() )
+ return -EOPNOTSUPP;
+
switch(op->u.set_para.ctrl_type)
{
case SCALING_MAX_FREQ:
--
generated by git-patchbot for /home/xen/git/xen.git#master