From 0ed2424b911f3a058dfea01b78817abed767433d Mon Sep 17 00:00:00 2001 From: Alexander Shishkin Date: Thu, 24 May 2018 11:27:27 +0300 Subject: [PATCH] intel_th: Use correct device when freeing buffers Commit d5c435df4a890 ("intel_th: msu: Use the real device in case of IOMMU domain allocation") changes dma buffer allocation to use the actual underlying device, but forgets to change the deallocation path, which leads to (if you've got CAP_SYS_RAWIO): > # echo 0,0 > /sys/bus/intel_th/devices/0-msc0/nr_pages > ------------[ cut here ]------------ > kernel BUG at ../linux/drivers/iommu/intel-iommu.c:3670! > CPU: 3 PID: 231 Comm: sh Not tainted 4.17.0-rc1+ #2729 > RIP: 0010:intel_unmap+0x11e/0x130 ... > Call Trace: > intel_free_coherent+0x3e/0x60 > msc_buffer_win_free+0x100/0x160 [intel_th_msu] This patch fixes the buffer deallocation code to use the correct device. Signed-off-by: Alexander Shishkin Fixes: d5c435df4a890 ("intel_th: msu: Use the real device in case of IOMMU domain allocation") Reported-by: Baofeng Tian CC: stable@vger.kernel.org # v4.14+ Signed-off-by: Greg Kroah-Hartman --- drivers/hwtracing/intel_th/msu.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/hwtracing/intel_th/msu.c b/drivers/hwtracing/intel_th/msu.c index ede388309376..634f58042c77 100644 --- a/drivers/hwtracing/intel_th/msu.c +++ b/drivers/hwtracing/intel_th/msu.c @@ -733,8 +733,8 @@ err_nomem: /* Reset the page to write-back before releasing */ set_memory_wb((unsigned long)win->block[i].bdesc, 1); #endif - dma_free_coherent(msc_dev(msc), size, win->block[i].bdesc, - win->block[i].addr); + dma_free_coherent(msc_dev(msc)->parent->parent, size, + win->block[i].bdesc, win->block[i].addr); } kfree(win); @@ -769,7 +769,7 @@ static void msc_buffer_win_free(struct msc *msc, struct msc_window *win) /* Reset the page to write-back before releasing */ set_memory_wb((unsigned long)win->block[i].bdesc, 1); #endif - dma_free_coherent(msc_dev(win->msc), PAGE_SIZE, + dma_free_coherent(msc_dev(win->msc)->parent->parent, PAGE_SIZE, win->block[i].bdesc, win->block[i].addr); }