s390/qdio: for_each macro correctness (dbb0dd02) · Commits · 戴 / test

I observed that there are for_each macros that do an extra memory access beyond the defined area. Normally this does not cause problems. But, this can cause exceptions. For example: if the area is allocated at the end of a page and the next page is not accessible. For correctness, I suggest changing the arguments of the 'for loop' like others 'for_each' do in the kernel. Signed-off-by:

Jose Alonso <joalonsof@gmail.com> Signed-off-by:

Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by:

Martin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/cio/qdio.h

+6 −8

Original line number	Original line	Diff line number	Diff line
	@@ -360,13 +360,11 @@ static inline int multicast_outbound(struct qdio_q *q)
	(unlikely(q->irq_ptr->siga_flag.sync_out_after_pci))		(unlikely(q->irq_ptr->siga_flag.sync_out_after_pci))

	#define for_each_input_queue(irq_ptr, q, i) \		#define for_each_input_queue(irq_ptr, q, i) \
	for (i = 0, q = irq_ptr->input_qs[0]; \		for (i = 0; i < irq_ptr->nr_input_qs && \
	i < irq_ptr->nr_input_qs; \		({ q = irq_ptr->input_qs[i]; 1; }); i++)
	q = irq_ptr->input_qs[++i])
	#define for_each_output_queue(irq_ptr, q, i) \		#define for_each_output_queue(irq_ptr, q, i) \
	for (i = 0, q = irq_ptr->output_qs[0]; \		for (i = 0; i < irq_ptr->nr_output_qs && \
	i < irq_ptr->nr_output_qs; \		({ q = irq_ptr->output_qs[i]; 1; }); i++)
	q = irq_ptr->output_qs[++i])

	#define prev_buf(bufnr) \		#define prev_buf(bufnr) \
	((bufnr + QDIO_MAX_BUFFERS_MASK) & QDIO_MAX_BUFFERS_MASK)		((bufnr + QDIO_MAX_BUFFERS_MASK) & QDIO_MAX_BUFFERS_MASK)

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