integer overflow in i2o_block

From: Meelis Roos
Date: Thu Jul 26 2007 - 16:30:26 EST


Got this warning on 32-bit ppc, seems real? And it seems I2O
subsystem has no maintainer (only DPT_I2O has one)?

CC [M] drivers/message/i2o/i2o_block.o
drivers/message/i2o/i2o_block.c: In function 'i2o_block_transfer':
drivers/message/i2o/i2o_block.c:837: warning: integer overflow in expression

The line in question is
msg->u.head[1] = cpu_to_le32(I2O_CMD_PRIVATE << 24 | HOST_TID << 12 | tid);
and I2O_CMD_PRIVATE is defined as 0xFF. This gets "0xFF0100 | tid" and
fits into 32-bit unsigned but not into 32-bit signed integer properly.
Target value head[*] is defined as u32 so the claculation does not fit
during computation? Should we mark the shiftable inputas as unsigned?

--
Meelis Roos (mroos@xxxxxxxx)
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