diff options
| author | Mark Brown <broonie@kernel.org> | 2026-01-28 11:22:06 +0000 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2026-01-28 11:22:06 +0000 |
| commit | 751ec6dd6773237bf480291ca894a696a2991c62 (patch) | |
| tree | 6ac1b53826f7836b3f7b29f3f17bb45d118535c0 /kernel/events/core.c | |
| parent | e540be7d56d740144b1bd6f220b61ffe2f3830d4 (diff) | |
| parent | 04f7516ab70f7b82aae1d2830af2ee6f17f3fe98 (diff) | |
spi: aspeed: Improve handling of shared SPI
Merge series from Chin-Ting Kuo <chin-ting_kuo@aspeedtech.com>:
This patch series improves handling of SPI controllers that are
shared by spi-mem devices and other SPI peripherals.
The primary goal of this series is to support non-spi-mem devices in
the ASPEED FMC/SPI controller driver. It also addresses an issue in
the spi-mem framework observed when different types of SPI devices
operate concurrently on the same controller, ensuring that spi-mem
operations are properly serialized.
Diffstat (limited to 'kernel/events/core.c')
| -rw-r--r-- | kernel/events/core.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c index 5b5cb620499e..a0fa488bce84 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -6997,6 +6997,15 @@ static int perf_mmap_rb(struct vm_area_struct *vma, struct perf_event *event, if (data_page_nr(event->rb) != nr_pages) return -EINVAL; + /* + * If this event doesn't have mmap_count, we're attempting to + * create an alias of another event's mmap(); this would mean + * both events will end up scribbling the same user_page; + * which makes no sense. + */ + if (!refcount_read(&event->mmap_count)) + return -EBUSY; + if (refcount_inc_not_zero(&event->rb->mmap_count)) { /* * Success -- managed to mmap() the same buffer |