Re: [PATCH] EDAC/altera: Silence an endian warning

[Borislav Petkov <bp@alien8.de>]

On Mon, Jun 24, 2019 at 03:27:55PM -0500, Thor Thayer wrote:
> Hi Dan,
> 
> On 6/24/19 8:47 AM, Dan Carpenter wrote:
> > Smatch complains that we're casting a u32 pointer to unsigned long.
> > 
> >      drivers/edac/altera_edac.c:1878 altr_edac_a10_irq_handler()
> >      warn: passing casted pointer '&irq_status' to 'find_first_bit()'
> > 
> > This code wouldn't work on a 64 bit big endian system because we would
> > read past the end of &irq_status.
> > 
> > Fixes: 13ab8448d2c9 ("EDAC, altera: Add ECC Manager IRQ controller support")
> > Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> > ---
> > Static analysis obviously and I don't know this subsystem at all.
> > Probably we're never going to run this on a 64 bit big endian system...
> > Feel free to ignore this if you want.
> > 
> >   drivers/edac/altera_edac.c | 4 +++-
> >   1 file changed, 3 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/edac/altera_edac.c b/drivers/edac/altera_edac.c
> > index c2e693e34d43..bf024ec0116c 100644
> > --- a/drivers/edac/altera_edac.c
> > +++ b/drivers/edac/altera_edac.c
> > @@ -1866,6 +1866,7 @@ static void altr_edac_a10_irq_handler(struct irq_desc *desc)
> >   	struct altr_arria10_edac *edac = irq_desc_get_handler_data(desc);
> >   	struct irq_chip *chip = irq_desc_get_chip(desc);
> >   	int irq = irq_desc_get_irq(desc);
> > +	unsigned long bits;
> >   	dberr = (irq = edac->db_irq) ? 1 : 0;
> >   	sm_offset = dberr ? A10_SYSMGR_ECC_INTSTAT_DERR_OFST :
> > @@ -1875,7 +1876,8 @@ static void altr_edac_a10_irq_handler(struct irq_desc *desc)
> >   	regmap_read(edac->ecc_mgr_map, sm_offset, &irq_status);
> > -	for_each_set_bit(bit, (unsigned long *)&irq_status, 32) {
> > +	bits = irq_status;
> > +	for_each_set_bit(bit, &bits, 32) {
> >   		irq = irq_linear_revmap(edac->domain, dberr * 32 + bit);
> >   		if (irq)
> >   			generic_handle_irq(irq);
> > 
> You are correct that we shouldn't use this on a 64 bit machine but this is a
> good fix. Thank you!
> 
> Reviewed-by: Thor Thayer <thor.thayer@linux.intel.com>

Applied, thanks.

-- 
Regards/Gruss,
    Boris.

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