From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S980623AbdDYGUM (ORCPT ); Tue, 25 Apr 2017 02:20:12 -0400 Received: from mail-pf0-f181.google.com ([209.85.192.181]:33752 "EHLO mail-pf0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S980601AbdDYGUE (ORCPT ); Tue, 25 Apr 2017 02:20:04 -0400 From: Alexandre Courbot To: Andrzej Pietrasiewicz , Jacek Anaszewski , Mauro Carvalho Chehab Cc: linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, Alexandre Courbot Subject: [PATCH] [media] s5p-jpeg: fix recursive spinlock acquisition Date: Tue, 25 Apr 2017 15:19:43 +0900 Message-Id: <20170425061943.717-1-acourbot@chromium.org> X-Mailer: git-send-email 2.13.0.rc0.306.g87b477812d-goog Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org v4l2_m2m_job_finish(), which is called from the interrupt handler with slock acquired, can call the device_run() hook immediately if another context was in the queue. This hook also acquires slock, resulting in a deadlock for this scenario. Fix this by releasing slock right before calling v4l2_m2m_job_finish(). This is safe to do as the state of the hardware cannot change before v4l2_m2m_job_finish() is called anyway. Signed-off-by: Alexandre Courbot --- drivers/media/platform/s5p-jpeg/jpeg-core.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/media/platform/s5p-jpeg/jpeg-core.c b/drivers/media/platform/s5p-jpeg/jpeg-core.c index 52dc7941db65..223b4379929e 100644 --- a/drivers/media/platform/s5p-jpeg/jpeg-core.c +++ b/drivers/media/platform/s5p-jpeg/jpeg-core.c @@ -2642,13 +2642,13 @@ static irqreturn_t s5p_jpeg_irq(int irq, void *dev_id) if (curr_ctx->mode == S5P_JPEG_ENCODE) vb2_set_plane_payload(&dst_buf->vb2_buf, 0, payload_size); v4l2_m2m_buf_done(dst_buf, state); - v4l2_m2m_job_finish(jpeg->m2m_dev, curr_ctx->fh.m2m_ctx); curr_ctx->subsampling = s5p_jpeg_get_subsampling_mode(jpeg->regs); spin_unlock(&jpeg->slock); s5p_jpeg_clear_int(jpeg->regs); + v4l2_m2m_job_finish(jpeg->m2m_dev, curr_ctx->fh.m2m_ctx); return IRQ_HANDLED; } @@ -2707,11 +2707,12 @@ static irqreturn_t exynos4_jpeg_irq(int irq, void *priv) v4l2_m2m_buf_done(dst_vb, VB2_BUF_STATE_ERROR); } - v4l2_m2m_job_finish(jpeg->m2m_dev, curr_ctx->fh.m2m_ctx); if (jpeg->variant->version == SJPEG_EXYNOS4) curr_ctx->subsampling = exynos4_jpeg_get_frame_fmt(jpeg->regs); spin_unlock(&jpeg->slock); + + v4l2_m2m_job_finish(jpeg->m2m_dev, curr_ctx->fh.m2m_ctx); return IRQ_HANDLED; } @@ -2770,10 +2771,15 @@ static irqreturn_t exynos3250_jpeg_irq(int irq, void *dev_id) if (curr_ctx->mode == S5P_JPEG_ENCODE) vb2_set_plane_payload(&dst_buf->vb2_buf, 0, payload_size); v4l2_m2m_buf_done(dst_buf, state); - v4l2_m2m_job_finish(jpeg->m2m_dev, curr_ctx->fh.m2m_ctx); curr_ctx->subsampling = exynos3250_jpeg_get_subsampling_mode(jpeg->regs); + + spin_unlock(&jpeg->slock); + + v4l2_m2m_job_finish(jpeg->m2m_dev, curr_ctx->fh.m2m_ctx); + return IRQ_HANDLED; + exit_unlock: spin_unlock(&jpeg->slock); return IRQ_HANDLED; -- 2.13.0.rc0.306.g87b477812d-goog