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@csgroup.eu
[ 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@g5.osdl.org
He re-iterated the same view recently in https://lore.kernel.org/all/CAHk-=wg2Pkb9kbfbstbB91AJA2SF6cySbsgHG-iQMq56j3V...
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@csgroup.eu Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://lore.kernel.org/r/4b8d4f96140af01dec3a3330924dda8b2451c316.167447679... Signed-off-by: Sasha Levin sashal@kernel.org
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.