This is a note to let you know that I've just added the patch titled mlxsw: i2c: Fix chunk size setting in output mailbox buffer to the 6.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: mlxsw-i2c-fix-chunk-size-setting-in-output-mailbox-b.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit e43b2aee31c8bb47eec56d8f24ba53df985908ba Author: Vadim Pasternak <vadimp@xxxxxxxxxx> Date: Thu Aug 24 15:43:08 2023 +0200 mlxsw: i2c: Fix chunk size setting in output mailbox buffer [ Upstream commit 146c7c330507c0384bf29d567186632bfe975927 ] The driver reads commands output from the output mailbox. If the size of the output mailbox is not a multiple of the transaction / block size, then the driver will not issue enough read transactions to read the entire output, which can result in driver initialization errors. Fix by determining the number of transactions using DIV_ROUND_UP(). Fixes: 3029a693beda ("mlxsw: i2c: Allow flexible setting of I2C transactions size") Signed-off-by: Vadim Pasternak <vadimp@xxxxxxxxxx> Reviewed-by: Ido Schimmel <idosch@xxxxxxxxxx> Signed-off-by: Petr Machata <petrm@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/ethernet/mellanox/mlxsw/i2c.c b/drivers/net/ethernet/mellanox/mlxsw/i2c.c index f5f5f8dc3d190..26e05f129e35a 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/i2c.c +++ b/drivers/net/ethernet/mellanox/mlxsw/i2c.c @@ -444,7 +444,7 @@ mlxsw_i2c_cmd(struct device *dev, u16 opcode, u32 in_mod, size_t in_mbox_size, } else { /* No input mailbox is case of initialization query command. */ reg_size = MLXSW_I2C_MAX_DATA_SIZE; - num = reg_size / mlxsw_i2c->block_size; + num = DIV_ROUND_UP(reg_size, mlxsw_i2c->block_size); if (mutex_lock_interruptible(&mlxsw_i2c->cmd.lock) < 0) { dev_err(&client->dev, "Could not acquire lock");