From: Greg KH <[email protected]> 3.5-stable review patch. If anyone has any objections, please let me know.
------------------ From: Robert Richter <[email protected]> commit bad9ac2d7f878a31cf1ae8c1ee3768077d222bcb upstream. Current implementation simply ignores attribute flags. Thus, there is no notification to userland of unsupported features. Check syscall's attribute flags to let userland know if a feature is supported by the kernel. This is also needed to distinguish between future kernels what might support a feature. Signed-off-by: Robert Richter <[email protected]> Signed-off-by: Peter Zijlstra <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- arch/x86/kernel/cpu/perf_event_amd_ibs.c | 12 ++++++++++++ include/linux/perf_event.h | 2 ++ 2 files changed, 14 insertions(+) --- a/arch/x86/kernel/cpu/perf_event_amd_ibs.c +++ b/arch/x86/kernel/cpu/perf_event_amd_ibs.c @@ -207,6 +207,15 @@ static int perf_ibs_precise_event(struct return -EOPNOTSUPP; } +static const struct perf_event_attr ibs_notsupp = { + .exclude_user = 1, + .exclude_kernel = 1, + .exclude_hv = 1, + .exclude_idle = 1, + .exclude_host = 1, + .exclude_guest = 1, +}; + static int perf_ibs_init(struct perf_event *event) { struct hw_perf_event *hwc = &event->hw; @@ -227,6 +236,9 @@ static int perf_ibs_init(struct perf_eve if (event->pmu != &perf_ibs->pmu) return -ENOENT; + if (perf_flags(&event->attr) & perf_flags(&ibs_notsupp)) + return -EINVAL; + if (config & ~perf_ibs->config_mask) return -EINVAL; --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -274,6 +274,8 @@ struct perf_event_attr { __u64 branch_sample_type; /* enum branch_sample_type */ }; +#define perf_flags(attr) (*(&(attr)->read_format + 1)) + /* * Ioctls that can be done on a perf event fd: */ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
