Re: [PATCH] Fix pSeries boot failure, by returning interrupt controller node when an interrupt-map property doesn't exist

On Tue, 30 Jun 2015 13:23:33 +1000
, Benjamin Herrenschmidt [off-list ref]
 wrote:

On Mon, 2015-06-29 at 18:50 -0500, Jeremy Linton wrote:

quoted

This is a reformat of the patch attached to "pSeries boot failure due
to wrong interrupt controller".

It allows of_irq_parse_raw() to return the node pointer of the
interrupt controller, rather than the parent bus. This allows
ics_rtas_host_match() to detect that the controller is a legacy 8259
and avoid using xics. This avoids an RTAS assertion/crash during early
kernel bootstrapping

Signed-off-by: Jeremy Linton <redacted>

Reviewed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---

Rob, do you want to take this or should we ?

Merged, thanks.

Jeremy, please check your mailer configuration. The patch was mangled
and would not apply. I had to fix it up manually.

Also, does this patch need to be backported into stable? What commit
introduced this bug, and which kernel does it first appear in?

Thanks,
g.

quoted

---
 drivers/of/irq.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/of/irq.c b/drivers/of/irq.c
index 1a79806..cb4b9ae 100644
--- a/drivers/of/irq.c
+++ b/drivers/of/irq.c

@@ -252,8 +252,6 @@ int of_irq_parse_raw(const __be32 *addr, struct

of_phandle_args *out_irq)
                 * Successfully parsed an interrrupt-map translation; copy new
                 * interrupt specifier into the out_irq structure
                 */
-               out_irq->np = newpar;
-
                match_array = imap - newaddrsize - newintsize;
                for (i = 0; i < newintsize; i++)
                        out_irq->args[i] = be32_to_cpup(imap - newintsize + i);

@@ -262,6 +260,7 @@ int of_irq_parse_raw(const __be32 *addr, struct

of_phandle_args *out_irq)

        skiplevel:
                /* Iterate again with new parent */
+               out_irq->np = newpar;
                pr_debug(" -> new parent: %s\n", of_node_full_name(newpar));
                of_node_put(ipar);
                ipar = newpar;
--
1.8.1.4