Linux-ARM-Kernel Archive on
 help / color / Atom feed
* [PATCH] soc: renesas: Add missing check for non-zero product register address
@ 2019-10-16 14:33 Geert Uytterhoeven
  2019-11-01 13:34 ` Geert Uytterhoeven
  0 siblings, 1 reply; 2+ messages in thread
From: Geert Uytterhoeven @ 2019-10-16 14:33 UTC (permalink / raw)
  To: Magnus Damm, Chris Brandt
  Cc: linux-renesas-soc, Geert Uytterhoeven, linux-arm-kernel

If the DTB for a device with an RZ/A2 SoC lacks a device node for the
BSID register, the ID validation code falls back to using a register at
address 0x0, which leads to undefined behavior (e.g. reading back a
random value).

This could be fixed by letting fam_rza2.reg point to the actual BSID
register.  However, the hardcoded fallbacks were meant for backwards
compatibility with old DTBs only, not for new SoCs.  Hence fix this by
validating renesas_family.reg before using it.

Fixes: 175f435f44b724e3 ("soc: renesas: identify RZ/A2")
Signed-off-by: Geert Uytterhoeven <>
 drivers/soc/renesas/renesas-soc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/soc/renesas/renesas-soc.c b/drivers/soc/renesas/renesas-soc.c
index 5dc2ae55f746a48a..85aaf85ce6b192d9 100644
--- a/drivers/soc/renesas/renesas-soc.c
+++ b/drivers/soc/renesas/renesas-soc.c
@@ -337,7 +337,7 @@ static int __init renesas_soc_init(void)
 	if (np) {
 		chipid = of_iomap(np, 0);
-	} else if (soc->id) {
+	} else if (soc->id && family->reg) {
 		chipid = ioremap(family->reg, 4);
 	if (chipid) {

linux-arm-kernel mailing list

^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, back to index

Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-10-16 14:33 [PATCH] soc: renesas: Add missing check for non-zero product register address Geert Uytterhoeven
2019-11-01 13:34 ` Geert Uytterhoeven

Linux-ARM-Kernel Archive on

Archives are clonable:
	git clone --mirror linux-arm-kernel/git/0.git
	git clone --mirror linux-arm-kernel/git/1.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-arm-kernel linux-arm-kernel/ \
	public-inbox-index linux-arm-kernel

Example config snippet for mirrors

Newsgroup available over NNTP:

AGPL code for this site: git clone