On Wed, Aug 07, 2019 at 08:49:52AM +0000, David Laight wrote:
From: Sasha LevinSent: 06 August 2019 22:33 From: Colin Ian King <colin.king@xxxxxxxxxxxxx> [ Upstream commit 1bbbab097a05276e312dd2462791d32b21ceb1ee ] Currently the retry counter is not being decremented, leading to a potential infinite spin if the scalar_reads don't change state. Addresses-Coverity: ("Infinite loop") Fixes: 280e54c9f614 ("drm/exynos: scaler: Reset hardware before starting the operation") Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx> Signed-off-by: Inki Dae <inki.dae@xxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/gpu/drm/exynos/exynos_drm_scaler.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/exynos/exynos_drm_scaler.c b/drivers/gpu/drm/exynos/exynos_drm_scaler.c index ec9c1b7d31033..8989f8af716b7 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_scaler.c +++ b/drivers/gpu/drm/exynos/exynos_drm_scaler.c @@ -94,12 +94,12 @@ static inline int scaler_reset(struct scaler_context *scaler) scaler_write(SCALER_CFG_SOFT_RESET, SCALER_CFG); do { cpu_relax(); - } while (retry > 1 && + } while (--retry > 1 && scaler_read(SCALER_CFG) & SCALER_CFG_SOFT_RESET); do { cpu_relax(); scaler_write(1, SCALER_INT_EN); - } while (retry > 0 && scaler_read(SCALER_INT_EN) != 1); + } while (--retry > 0 && scaler_read(SCALER_INT_EN) != 1); return retry ? 0 : -EIO;If the first loop hits the retry limit the second loop won't be right and the final return value will be 0.
This looks like an upstream problem as well, no? -- Thanks, Sasha _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
