The vdec_1 firmware loader used static variables for DMA buffer addresses (`mc_addr`, `mc_addr_map`). This made allocations global across sessions, corrupting state when multiple decoders loaded firmware concurrently. Under stress this triggered KASAN reports, lost references, and memory leaks. Making mc_addr and mc_addr_map local to each load call, eliminating cross‑session races.
The firmware DMA completion check also relied on a raw decrement loop of 1000 iterations. On modern CPUs this loop completed far too quickly, often before hardware signaled ready, producing false "DMA hang" errors. Replacing the busy‑wait loop with readl_poll_timeout_atomic(), providing a bounded, microsecond scale poll with proper timeout semantics. Cc: Nicolas Dufresne <[email protected]> Signed-off-by: Anand Moon <[email protected]> --- drivers/staging/media/meson/vdec/vdec_1.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/drivers/staging/media/meson/vdec/vdec_1.c b/drivers/staging/media/meson/vdec/vdec_1.c index a65cb49594465..27363c9a5af3c 100644 --- a/drivers/staging/media/meson/vdec/vdec_1.c +++ b/drivers/staging/media/meson/vdec/vdec_1.c @@ -29,14 +29,14 @@ vdec_1_load_firmware(struct amvdec_session *sess, const char *fwname) struct amvdec_core *core = sess->core; struct device *dev = core->dev_dec; struct amvdec_codec_ops *codec_ops = sess->fmt_out->codec_ops; - static void *mc_addr; - static dma_addr_t mc_addr_map; + void *mc_addr; + dma_addr_t mc_addr_map; int ret; - u32 i = 1000; + u32 val; ret = request_firmware(&fw, fwname, dev); if (ret < 0) - return -EINVAL; + return ret; if (fw->size < MC_SIZE) { dev_err(dev, "Firmware size %zu is too small. Expected %u.\n", @@ -63,11 +63,11 @@ vdec_1_load_firmware(struct amvdec_session *sess, const char *fwname) amvdec_write_dos(core, IMEM_DMA_COUNT, MC_SIZE / 4); amvdec_write_dos(core, IMEM_DMA_CTRL, (0x8000 | (7 << 16))); - while (--i && amvdec_read_dos(core, IMEM_DMA_CTRL) & 0x8000); - - if (i == 0) { + ret = readl_poll_timeout_atomic(core->dos_base + IMEM_DMA_CTRL, val, + !(val & 0x8000), 10, 10000); + if (ret) { dev_err(dev, "Firmware load fail (DMA hang?)\n"); - ret = -EINVAL; + ret = -ETIMEDOUT; goto free_mc; } -- 2.50.1
