Messages in this thread Patch in this message | ![/](/images/icornerl.gif) | | From | Rex Nie <> | Subject | [PATCH] fs/resctrl: fix domid loss precision issue | Date | Mon, 11 Mar 2024 14:48:22 +0800 |
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Below statement from mkdir_mondata_subdir function will loss precision, because it assigns int to 14 bits bitfield. priv.u.domid = d->id;
This will cause below issue if cache_id > 0x3fff likes: /sys/fs/resctrl/mon_groups/p1/mon_data/mon_L3_1048564 # cat llc_occupancy cat: read error: No such file or directory
This is the call trace when cat llc_occupancy: rdtgroup_mondata_show() domid = md.u.domid d = resctrl_arch_find_domain(r, domid)
d is null here because of lossing precision
Signed-off-by: Rex Nie <rex.nie@jaguarmicro.com> Signed-off-by: Liming Wu <liming.wu@jaguar.com> --- fs/resctrl/internal.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/resctrl/internal.h b/fs/resctrl/internal.h index 7a6f46b4edd0..096317610949 100644 --- a/fs/resctrl/internal.h +++ b/fs/resctrl/internal.h @@ -94,7 +94,7 @@ union mon_data_bits { struct { unsigned int rid : 10; enum resctrl_event_id evtid : 8; - unsigned int domid : 14; + u32 domid; } u; }; -- 2.34.1
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