This is a note to let you know that I've just added the patch titled
net/mlx4_en: Fix type mismatch for 32-bit systems
to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: net-mlx4_en-fix-type-mismatch-for-32-bit-systems.patch and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From foo@baz Wed Dec 6 17:39:55 CET 2017
From: Slava Shwartsman slavash@mellanox.com Date: Thu, 29 Dec 2016 18:37:12 +0200 Subject: net/mlx4_en: Fix type mismatch for 32-bit systems
From: Slava Shwartsman slavash@mellanox.com
[ Upstream commit 61b6034c6cfdcb265bb453505c3d688e7567727a ]
is_power_of_2 expects unsigned long and we pass u64 max_val_cycles, this will be truncated on 32 bit systems, and the result is not what we were expecting. div_u64 expects u32 as a second argument and we pass max_val_cycles_rounded which is u64 hence it will always be truncated. Fix was tested on both 64 and 32 bit systems and got same results for max_val_cycles and max_val_cycles_rounded.
Fixes: 4850cf458157 ("net/mlx4_en: Resolve dividing by zero in 32-bit system") Signed-off-by: Slava Shwartsman slavash@mellanox.com Signed-off-by: Tariq Toukan tariqt@mellanox.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin alexander.levin@verizon.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/mellanox/mlx4/en_clock.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-)
--- a/drivers/net/ethernet/mellanox/mlx4/en_clock.c +++ b/drivers/net/ethernet/mellanox/mlx4/en_clock.c @@ -251,13 +251,9 @@ static u32 freq_to_shift(u16 freq) { u32 freq_khz = freq * 1000; u64 max_val_cycles = freq_khz * 1000 * MLX4_EN_WRAP_AROUND_SEC; - u64 tmp_rounded = - roundup_pow_of_two(max_val_cycles) > max_val_cycles ? - roundup_pow_of_two(max_val_cycles) - 1 : UINT_MAX; - u64 max_val_cycles_rounded = is_power_of_2(max_val_cycles + 1) ? - max_val_cycles : tmp_rounded; + u64 max_val_cycles_rounded = 1ULL << fls64(max_val_cycles - 1); /* calculate max possible multiplier in order to fit in 64bit */ - u64 max_mul = div_u64(0xffffffffffffffffULL, max_val_cycles_rounded); + u64 max_mul = div64_u64(ULLONG_MAX, max_val_cycles_rounded);
/* This comes from the reverse of clocksource_khz2mult */ return ilog2(div_u64(max_mul * freq_khz, 1000000));
Patches currently in stable-queue which might be from slavash@mellanox.com are
queue-4.9/net-mlx4_en-fix-type-mismatch-for-32-bit-systems.patch