Commit 20648430 authored by Ekansh Gupta's avatar Ekansh Gupta Committed by Greg Kroah-Hartman
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misc: fastrpc: Free DMA handles for RPC calls with no arguments 



The FDs for DMA handles to be freed is updated in fdlist by DSP over
a remote call. This holds true even for remote calls with no
arguments. To handle this, get_args and put_args are needed to
be called for remote calls with no arguments also as fdlist
is allocated in get_args and FDs updated in fdlist is freed
in put_args.

Fixes: 8f6c1d8c ("misc: fastrpc: Add fdlist implementation")
Cc: stable <stable@kernel.org>
Signed-off-by: default avatarEkansh Gupta <quic_ekangupt@quicinc.com>
Signed-off-by: default avatarSrinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20231013122007.174464-3-srinivas.kandagatla@linaro.org


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 1c29d801

drivers/misc/fastrpc.c

+10 −13
Original line number Diff line number Diff line
@@ -1091,6 +1091,7 @@ static int fastrpc_put_args(struct fastrpc_invoke_ctx *ctx, 
		}

	}



	/* Clean up fdlist which is updated by DSP */

	for (i = 0; i < FASTRPC_MAX_FDLIST; i++) {

		if (!fdlist[i])

			break;
@@ -1157,11 +1158,9 @@ static int fastrpc_internal_invoke(struct fastrpc_user *fl, u32 kernel, 
	if (IS_ERR(ctx))

		return PTR_ERR(ctx);



	if (ctx->nscalars) {

	err = fastrpc_get_args(kernel, ctx);

	if (err)

		goto bail;

	}



	/* make sure that all CPU memory writes are seen by DSP */

	dma_wmb();
@@ -1185,14 +1184,12 @@ static int fastrpc_internal_invoke(struct fastrpc_user *fl, u32 kernel, 
	if (err)

		goto bail;



	if (ctx->nscalars) {

	/* make sure that all memory writes by DSP are seen by CPU */

	dma_rmb();

	/* populate all the output buffers with results */

	err = fastrpc_put_args(ctx, kernel);

	if (err)

		goto bail;

	}



bail:

	if (err != -ERESTARTSYS && err != -ETIMEDOUT) {