This is a note to let you know that I've just added the patch titled
intel_th: msu: Fix vmalloced buffers
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
intel_th-msu-fix-vmalloced-buffers.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 302c759318099f4625360b90947f6a6397d995c0
Author: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Date: Tue Jul 5 11:26:34 2022 +0300
intel_th: msu: Fix vmalloced buffers
[ Upstream commit ac12ad3ccf6d386e64a9d6a890595a2509d24edd ]
After commit f5ff79fddf0e ("dma-mapping: remove CONFIG_DMA_REMAP") there's
a chance of DMA buffer getting allocated via vmalloc(), which messes up
the mmapping code:
> RIP: msc_mmap_fault [intel_th_msu]
> Call Trace:
> <TASK>
> __do_fault
> do_fault
...
Fix this by accounting for vmalloc possibility.
Fixes: ba39bd830605 ("intel_th: msu: Switch over to scatterlist")
Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Signed-off-by: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220705082637.59979-4-alexander.shishkin@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/hwtracing/intel_th/msu.c b/drivers/hwtracing/intel_th/msu.c
index 3cd2489d398c..640b0aae7eb4 100644
--- a/drivers/hwtracing/intel_th/msu.c
+++ b/drivers/hwtracing/intel_th/msu.c
@@ -1050,6 +1050,16 @@ msc_buffer_set_uc(struct msc_window *win, unsigned int nr_segs) {}
static inline void msc_buffer_set_wb(struct msc_window *win) {}
#endif /* CONFIG_X86 */
+static struct page *msc_sg_page(struct scatterlist *sg)
+{
+ void *addr = sg_virt(sg);
+
+ if (is_vmalloc_addr(addr))
+ return vmalloc_to_page(addr);
+
+ return sg_page(sg);
+}
+
/**
* msc_buffer_win_alloc() - alloc a window for a multiblock mode
* @msc: MSC device
@@ -1122,7 +1132,7 @@ static void __msc_buffer_win_free(struct msc *msc, struct msc_window *win)
int i;
for_each_sg(win->sgt->sgl, sg, win->nr_segs, i) {
- struct page *page = sg_page(sg);
+ struct page *page = msc_sg_page(sg);
page->mapping = NULL;
dma_free_coherent(msc_dev(win->msc)->parent->parent, PAGE_SIZE,
@@ -1384,7 +1394,7 @@ static struct page *msc_buffer_get_page(struct msc *msc, unsigned long pgoff)
pgoff -= win->pgoff;
for_each_sg(win->sgt->sgl, sg, win->nr_segs, blk) {
- struct page *page = sg_page(sg);
+ struct page *page = msc_sg_page(sg);
size_t pgsz = PFN_DOWN(sg->length);
if (pgoff < pgsz)
