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authorJakub Kicinski <kuba@kernel.org>2023-12-14 17:13:35 -0800
committerJakub Kicinski <kuba@kernel.org>2023-12-14 17:14:41 -0800
commit8f674972d698c1223b6b4f374df5dde835b88c34 (patch)
treee6ec59ecb3b42b333416dfc10e738689199811f4 /kernel/events/core.c
parent1b666016d0ad4a879dcd3d9188635ad68c4b16ce (diff)
parentc7402612e2e61b76177f22e6e7f705adcbecc6fe (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. Conflicts: drivers/net/ethernet/intel/iavf/iavf_ethtool.c 3a0b5a2929fd ("iavf: Introduce new state machines for flow director") 95260816b489 ("iavf: use iavf_schedule_aq_request() helper") https://lore.kernel.org/all/84e12519-04dc-bd80-bc34-8cf50d7898ce@intel.com/ drivers/net/ethernet/broadcom/bnxt/bnxt.c c13e268c0768 ("bnxt_en: Fix HWTSTAMP_FILTER_ALL packet timestamp logic") c2f8063309da ("bnxt_en: Refactor RX VLAN acceleration logic.") a7445d69809f ("bnxt_en: Add support for new RX and TPA_START completion types for P7") 1c7fd6ee2fe4 ("bnxt_en: Rename some macros for the P5 chips") https://lore.kernel.org/all/20231211110022.27926ad9@canb.auug.org.au/ drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.c bd6781c18cb5 ("bnxt_en: Fix wrong return value check in bnxt_close_nic()") 84793a499578 ("bnxt_en: Skip nic close/open when configuring tstamp filters") https://lore.kernel.org/all/20231214113041.3a0c003c@canb.auug.org.au/ drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c 3d7a3f2612d7 ("net/mlx5: Nack sync reset request when HotPlug is enabled") cecf44ea1a1f ("net/mlx5: Allow sync reset flow when BF MGT interface device is present") https://lore.kernel.org/all/20231211110328.76c925af@canb.auug.org.au/ No adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'kernel/events/core.c')
-rw-r--r--kernel/events/core.c61
1 files changed, 38 insertions, 23 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c
index b704d83a28b2..c9d123e13b57 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -1814,31 +1814,34 @@ static inline void perf_event__state_init(struct perf_event *event)
PERF_EVENT_STATE_INACTIVE;
}
-static void __perf_event_read_size(struct perf_event *event, int nr_siblings)
+static int __perf_event_read_size(u64 read_format, int nr_siblings)
{
int entry = sizeof(u64); /* value */
int size = 0;
int nr = 1;
- if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
+ if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
size += sizeof(u64);
- if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
+ if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
size += sizeof(u64);
- if (event->attr.read_format & PERF_FORMAT_ID)
+ if (read_format & PERF_FORMAT_ID)
entry += sizeof(u64);
- if (event->attr.read_format & PERF_FORMAT_LOST)
+ if (read_format & PERF_FORMAT_LOST)
entry += sizeof(u64);
- if (event->attr.read_format & PERF_FORMAT_GROUP) {
+ if (read_format & PERF_FORMAT_GROUP) {
nr += nr_siblings;
size += sizeof(u64);
}
- size += entry * nr;
- event->read_size = size;
+ /*
+ * Since perf_event_validate_size() limits this to 16k and inhibits
+ * adding more siblings, this will never overflow.
+ */
+ return size + nr * entry;
}
static void __perf_event_header_size(struct perf_event *event, u64 sample_type)
@@ -1888,8 +1891,9 @@ static void __perf_event_header_size(struct perf_event *event, u64 sample_type)
*/
static void perf_event__header_size(struct perf_event *event)
{
- __perf_event_read_size(event,
- event->group_leader->nr_siblings);
+ event->read_size =
+ __perf_event_read_size(event->attr.read_format,
+ event->group_leader->nr_siblings);
__perf_event_header_size(event, event->attr.sample_type);
}
@@ -1920,24 +1924,35 @@ static void perf_event__id_header_size(struct perf_event *event)
event->id_header_size = size;
}
+/*
+ * Check that adding an event to the group does not result in anybody
+ * overflowing the 64k event limit imposed by the output buffer.
+ *
+ * Specifically, check that the read_size for the event does not exceed 16k,
+ * read_size being the one term that grows with groups size. Since read_size
+ * depends on per-event read_format, also (re)check the existing events.
+ *
+ * This leaves 48k for the constant size fields and things like callchains,
+ * branch stacks and register sets.
+ */
static bool perf_event_validate_size(struct perf_event *event)
{
- /*
- * The values computed here will be over-written when we actually
- * attach the event.
- */
- __perf_event_read_size(event, event->group_leader->nr_siblings + 1);
- __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ);
- perf_event__id_header_size(event);
+ struct perf_event *sibling, *group_leader = event->group_leader;
- /*
- * Sum the lot; should not exceed the 64k limit we have on records.
- * Conservative limit to allow for callchains and other variable fields.
- */
- if (event->read_size + event->header_size +
- event->id_header_size + sizeof(struct perf_event_header) >= 16*1024)
+ if (__perf_event_read_size(event->attr.read_format,
+ group_leader->nr_siblings + 1) > 16*1024)
return false;
+ if (__perf_event_read_size(group_leader->attr.read_format,
+ group_leader->nr_siblings + 1) > 16*1024)
+ return false;
+
+ for_each_sibling_event(sibling, group_leader) {
+ if (__perf_event_read_size(sibling->attr.read_format,
+ group_leader->nr_siblings + 1) > 16*1024)
+ return false;
+ }
+
return true;
}