perf intel-pt: Fix aux_watermark calculation for 64-bit size

ahunter6 · namhyung · commit a89a26ecb706 · 2024-07-02T15:24:01.000-07:00
aux_watermark is a u32. For a 64-bit size, cap the aux_watermark calculation at UINT_MAX instead of truncating it to 32-bits. Fixes: e89bf1f ("perf intel-pt: Use aux_watermark") Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Link: https://lore.kernel.org/r/20240625104532.11990-2-adrian.hunter@intel.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
diff --git a/tools/perf/arch/x86/util/intel-pt.c b/tools/perf/arch/x86/util/intel-pt.c
@@ -758,7 +758,8 @@ static int intel_pt_recording_options(struct auxtrace_record *itr,
 	}
 
 	if (!opts->auxtrace_snapshot_mode && !opts->auxtrace_sample_mode) {
-		u32 aux_watermark = opts->auxtrace_mmap_pages * page_size / 4;
+		size_t aw = opts->auxtrace_mmap_pages * (size_t)page_size / 4;
+		u32 aux_watermark = aw > UINT_MAX ? UINT_MAX : aw;
 
 		intel_pt_evsel->core.attr.aux_watermark = aux_watermark;
 	}

Original file line number	Diff line number	Diff line change
`@@ -758,7 +758,8 @@ static int intel_pt_recording_options(struct auxtrace_record *itr,`
`758`	`758`	`}`
`759`	`759`
`760`	`760`	`if (!opts->auxtrace_snapshot_mode && !opts->auxtrace_sample_mode) {`
`761`		`- u32 aux_watermark = opts->auxtrace_mmap_pages * page_size / 4;`
	`761`	`+ size_t aw = opts->auxtrace_mmap_pages * (size_t)page_size / 4;`
	`762`	`+ u32 aux_watermark = aw > UINT_MAX ? UINT_MAX : aw;`
`762`	`763`
`763`	`764`	`intel_pt_evsel->core.attr.aux_watermark = aux_watermark;`
`764`	`765`	`}`