Subject: Re: linux-next: [PATCH] infiniband/hw/ipath/ipath_sdma.c , fix compiler warnings

From: [email-masked] (Tony Breeds)
Date: Thu, 22 May 2008 10:23:35 +1000

On Wed, May 21, 2008 at 04:06:36PM +0200, Gabriel C wrote:
> On linux-next from today , allmodconfig, I see the following warnings on 64bit:

x86_64 right?

<snip>

> diff --git a/drivers/infiniband/hw/ipath/ipath_sdma.c b/drivers/infiniband/hw/ipath/ipath_sdma.c
> index 3697449..5f80151 100644
> --- a/drivers/infiniband/hw/ipath/ipath_sdma.c
> +++ b/drivers/infiniband/hw/ipath/ipath_sdma.c
> @@ -257,7 +257,7 @@ static void sdma_abort_task(unsigned long opaque)
>  	/* everything is stopped, time to clean up and restart */
>  	if (status == IPATH_SDMA_ABORT_ABORTED) {
>  		struct ipath_sdma_txreq *txp, *txpnext;
> -		u64 hwstatus;
> +		unsigned long hwstatus;
>  		int notify = 0;
>  
>  		hwstatus = ipath_read_kreg64(dd,

This can't be right.  hwstatus needs to be u64, as that's what ipath_read_kreg64() retuns.
and a little bit further down we see:

---
if (/* ScoreBoardDrainInProg */
    test_bit(63, &hwstatus) ||
    /* AbortInProg */
    test_bit(62, &hwstatus) ||
    /* InternalSDmaEnable */
    test_bit(61, &hwstatus) ||
---

so hwstatus, clearly needs to be 64-bits.  This brings up an interesting
point.  test_bit() and co are essntally expecting to be passed the address
of an unsigned long[], so is it correct to pass &u64?

Yours Tony

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