[PATCH v1 1/2] misc: fastrpc: Fix registered buffer page address

[Ekansh Gupta]

For registered  buffers, fastrpc driver sends the buffer information
to remote subsystem. There is a problem with current implementation
where the page address is being sent with an offset leading to
improper buffer address on DSP. This is leads to functional failures
as DSP expects base address in page information and extracts offset
information from remote arguments. Mask the offset and pass the base
page address to DSP.

Fixes: 80f3afd72bd4 ("misc: fastrpc: consider address offset before sending to DSP")
Cc: stable <stable at kernel.org>
Signed-off-by: Ekansh Gupta <quic_ekangupt at quicinc.com>
---
 drivers/misc/fastrpc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c
index 48d08eeb2d20..cfa1546c9e3f 100644
--- a/drivers/misc/fastrpc.c
+++ b/drivers/misc/fastrpc.c
@@ -992,7 +992,7 @@ static int fastrpc_get_args(u32 kernel, struct fastrpc_invoke_ctx *ctx)
 			mmap_read_lock(current->mm);
 			vma = find_vma(current->mm, ctx->args[i].ptr);
 			if (vma)
-				pages[i].addr += ctx->args[i].ptr -
+				pages[i].addr += (ctx->args[i].ptr & PAGE_MASK) -
 						 vma->vm_start;
 			mmap_read_unlock(current->mm);
 
-- 
2.34.1