On Wed, Mar 15, 2023 at 12:32:27PM +0000, Christophe Leroy wrote:
Le 15/03/2023 à 13:12, Greg Kroah-Hartman a écrit :
From: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
[ Upstream commit bab537805a10bdbf55b31324ba4a9599e0651e5e ]
NO_IRQ is a relic from the old days. It is not used anymore in core
functions. By the way, function irq_of_parse_and_map() returns value 0
on error.
In some drivers, NO_IRQ is erroneously used to check the return of
irq_of_parse_and_map().
It is not a real bug today because the only architectures using the
drivers being fixed by this patch define NO_IRQ as 0, but there are
architectures which define NO_IRQ as -1. If one day those
architectures start using the non fixed drivers, there will be a
problem.
Long time ago Linus advocated for not using NO_IRQ, see
https://lore.kernel.org/all/Pine.LNX.4.64.0511211150040.13959@xxxxxxxxxxx
He re-iterated the same view recently in
https://lore.kernel.org/all/CAHk-=wg2Pkb9kbfbstbB91AJA2SF6cySbsgHG-iQMq56j3VTcA@xxxxxxxxxxxxxx
So test !irq instead of tesing irq == NO_IRQ.
All other usage of NO_IRQ for powerpc were removed in previous cycles so
the time has come to remove NO_IRQ completely for powerpc.
Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/4b8d4f96140af01dec3a3330924dda8b2451c316.1674476798.git.christophe.leroy@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
Same, you can't remove NO_IRQ macro without first all preparation
patches merged during the 6.2 cycle.
Ack, I'll drop this one.
--
Thanks,
Sasha
