[PATCH] thunderbolt: Make priority unsigned in struct tb_path

From: Nathan Chancellor <natechancellor@gmail.com>
To: Andreas Noever <andreas.noever@gmail.com>,
	Michael Jamet <michael.jamet@intel.com>,
	Mika Westerberg <mika.westerberg@linux.intel.com>,
	Yehezkel Bernat <YehezkelShB@gmail.com>
Cc: linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com,
	Nick Desaulniers <ndesaulniers@google.com>,
	Nathan Chancellor <natechancellor@gmail.com>
Subject: [PATCH] thunderbolt: Make priority unsigned in struct tb_path
Date: Wed, 24 Apr 2019 11:34:13 -0700	[thread overview]
Message-ID: <20190424183413.13854-1-natechancellor@gmail.com> (raw)

Clang warns:

drivers/thunderbolt/tunnel.c:504:17: warning: implicit truncation from
'int' to bit-field changes value from 5 to -3
[-Wbitfield-constant-conversion]
        path->priority = 5;
                       ^ ~
1 warning generated.

The priority member in struct tb_path is only ever assigned a positive
number:

$ rg -n priority drivers/thunderbolt/path.c
drivers/thunderbolt/tunnel.c:99:        path->priority = 3;
drivers/thunderbolt/tunnel.c:308:       path->priority = 2;
drivers/thunderbolt/tunnel.c:323:       path->priority = 1;
drivers/thunderbolt/tunnel.c:504:       path->priority = 5;

Furthmore, that value is only assigned to an unsigned integer in
tb_path_activate (the priority member in struct tb_regs_hop).

Fixes: 44242d6c9703 ("thunderbolt: Add support for DMA tunnels")
Link: https://github.com/ClangBuiltLinux/linux/issues/454
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
---
 drivers/thunderbolt/tb.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
index 15d225dcb403..b12c8f33d89c 100644
--- a/drivers/thunderbolt/tb.h
+++ b/drivers/thunderbolt/tb.h
@@ -225,7 +225,7 @@ struct tb_path {
 	enum tb_path_port ingress_fc_enable;
 	enum tb_path_port egress_fc_enable;
 
-	int priority:3;
+	unsigned int priority:3;
 	int weight:4;
 	bool drop_packages;
 	bool activated;
-- 
2.21.0

