EDAC/altera: Use the proper type for the IRQ status bits

BugLink: https://bugs.launchpad.net/bugs/1848046
[ Upstream commit 8faa1cf6ed82f33009f63986c3776cc48af1b7b2 ]

Smatch complains about the cast of 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 it would
read past the end of &irq_status.

 [ bp: massage. ]

Fixes: 13ab8448d2c9 ("EDAC, altera: Add ECC Manager IRQ controller support")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thor Thayer <thor.thayer@linux.intel.com>
Cc: James Morse <james.morse@arm.com>
Cc: kernel-janitors@vger.kernel.org
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20190624134717.GA1754@mwanda
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

diff --git a/drivers/edac/altera_edac.c b/drivers/edac/altera_edac.c
index c2e693e34d434e53c801546d02700e5ee219644f..bf024ec0116c779848308e22d1c14f4655211951 100644 (file)
--- 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);