6.12-stable review patch. If anyone has any objections, please let me know.
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From: Namhyung Kim namhyung@kernel.org
[ Upstream commit 35d13f841a3d8159ef20d5e32a9ed3faa27875bc ]
The previous change to support cgroup filters introduced a bug that pathname can include commas. It confused the lexer to treat an item and the trailing comma as a single token. And it resulted in a parse error:
$ sudo perf record -e cycles:P --filter 'period > 0, ip > 64' -- true perf_bpf_filter: Error: Unexpected item: 0, perf_bpf_filter: syntax error, unexpected BFT_ERROR, expecting BFT_NUM
Usage: perf record [<options>] [<command>] or: perf record [<options>] -- <command> [<options>]
--filter <filter> event filter
It should get "0" and "," separately.
An easiest fix would be to remove "," from the possible pathname characters. As it's for cgroup names, probably ok to assume it won't have commas in the pathname.
I found that the existing BPF filtering test didn't have any complex filter condition with commas. Let's update the group filter test which is supposed to test filter combinations like this.
Link: https://lore.kernel.org/r/20250307220922.434319-1-namhyung@kernel.org Fixes: 91e88437d5156b20 ("perf bpf-filter: Support filtering on cgroups") Reported-by: Sally Shi sshii@google.com Signed-off-by: Namhyung Kim namhyung@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- tools/perf/tests/shell/record_bpf_filter.sh | 4 ++-- tools/perf/util/bpf-filter.l | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/tools/perf/tests/shell/record_bpf_filter.sh b/tools/perf/tests/shell/record_bpf_filter.sh index 1b58ccc1fd882..4d6c3c1b7fb92 100755 --- a/tools/perf/tests/shell/record_bpf_filter.sh +++ b/tools/perf/tests/shell/record_bpf_filter.sh @@ -89,7 +89,7 @@ test_bpf_filter_fail() { test_bpf_filter_group() { echo "Group bpf-filter test"
- if ! perf record -e task-clock --filter 'period > 1000 || ip > 0' \ + if ! perf record -e task-clock --filter 'period > 1000, ip > 0' \ -o /dev/null true 2>/dev/null then echo "Group bpf-filter test [Failed should succeed]" @@ -97,7 +97,7 @@ test_bpf_filter_group() { return fi
- if ! perf record -e task-clock --filter 'cpu > 0 || ip > 0' \ + if ! perf record -e task-clock --filter 'period > 1000 , cpu > 0 || ip > 0' \ -o /dev/null true 2>&1 | grep -q PERF_SAMPLE_CPU then echo "Group bpf-filter test [Failed forbidden CPU]" diff --git a/tools/perf/util/bpf-filter.l b/tools/perf/util/bpf-filter.l index f313404f95a90..6aa65ade33851 100644 --- a/tools/perf/util/bpf-filter.l +++ b/tools/perf/util/bpf-filter.l @@ -76,7 +76,7 @@ static int path_or_error(void) num_dec [0-9]+ num_hex 0[Xx][0-9a-fA-F]+ space [ \t]+ -path [^ \t\n]+ +path [^ \t\n,]+ ident [_a-zA-Z][_a-zA-Z0-9]+
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