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authorKees Cook2018-09-13 23:23:56 +0200
committerDavid S. Miller2018-09-14 01:53:24 +0200
commitee4fccbee7d397c4d937e20d8c76212ffc23a7e3 (patch)
treeed87fd2701be59b42b3f8676b22674eed0ff08fc /drivers/net/ethernet/ibm/emac/core.h
parentpktgen: Fix fall-through annotation (diff)
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net/ibm/emac: Remove VLA usage
In the quest to remove all stack VLA usage from the kernel[1], this removes the VLA used for the emac xaht registers size. Since the size of registers can only ever be 4 or 8, as detected in emac_init_config(), the max can be hardcoded and a runtime test added for robustness. [1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com Cc: "David S. Miller" <davem@davemloft.net> Cc: Christian Lamparter <chunkeey@gmail.com> Cc: Ivan Mikhaylov <ivan@de.ibm.com> Cc: netdev@vger.kernel.org Co-developed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet/ibm/emac/core.h')
-rw-r--r--drivers/net/ethernet/ibm/emac/core.h3
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/net/ethernet/ibm/emac/core.h b/drivers/net/ethernet/ibm/emac/core.h
index 369de2cfb15b..84caa4a3fc52 100644
--- a/drivers/net/ethernet/ibm/emac/core.h
+++ b/drivers/net/ethernet/ibm/emac/core.h
@@ -390,6 +390,9 @@ static inline int emac_has_feature(struct emac_instance *dev,
#define EMAC4SYNC_XAHT_SLOTS_SHIFT 8
#define EMAC4SYNC_XAHT_WIDTH_SHIFT 5
+/* The largest span between slots and widths above is 3 */
+#define EMAC_XAHT_MAX_REGS (1 << 3)
+
#define EMAC_XAHT_SLOTS(dev) (1 << (dev)->xaht_slots_shift)
#define EMAC_XAHT_WIDTH(dev) (1 << (dev)->xaht_width_shift)
#define EMAC_XAHT_REGS(dev) (1 << ((dev)->xaht_slots_shift - \