From 31c8025fac3d8bbff7ce4602338d88efc2d7972c Mon Sep 17 00:00:00 2001 From: David Brazdil Date: Fri, 17 Sep 2021 14:14:23 +0100 Subject: [PATCH] of: restricted dma: Fix condition for rmem init of_dma_set_restricted_buffer fails to handle negative return values from of_property_count_elems_of_size, e.g. when the property does not exist. This results in an attempt to assign a non-existent reserved memory region to the device and a warning being printed. Fix the condition to take negative values into account. Fixes: f3cfd136aef0 ("of: restricted dma: Don't fail device probe on rmem init failure") Cc: Will Deacon Signed-off-by: David Brazdil Acked-by: Will Deacon Link: https://lore.kernel.org/r/20210917131423.2760155-1-dbrazdil@google.com Signed-off-by: Rob Herring --- drivers/of/device.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/of/device.c b/drivers/of/device.c index 5b043ee30824..b0800c260f64 100644 --- a/drivers/of/device.c +++ b/drivers/of/device.c @@ -85,7 +85,11 @@ of_dma_set_restricted_buffer(struct device *dev, struct device_node *np) break; } - if (i != count && of_reserved_mem_device_init_by_idx(dev, of_node, i)) + /* + * Attempt to initialize a restricted-dma-pool region if one was found. + * Note that count can hold a negative error code. + */ + if (i < count && of_reserved_mem_device_init_by_idx(dev, of_node, i)) dev_warn(dev, "failed to initialise \"restricted-dma-pool\" memory node\n"); }