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Message-ID: <d7412ef9-8e25-4f55-aac9-8ec479fb6775@draconx.ca>
Date: Wed, 29 May 2024 01:36:28 -0400
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Subject: Re: PROBLEM: kbd busted in linux 6.10-rc1 (regression)
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To: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-kernel@vger.kernel.org,
 Linux regressions mailing list <regressions@lists.linux.dev>,
 Alexey Gladkov <legion@kernel.org>,
 Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
 Linus Torvalds <torvalds@linux-foundation.org>
References: <ad4e561c-1d49-4f25-882c-7a36c6b1b5c0@draconx.ca>
 <20240529052543.GL2118490@ZenIV>
From: Nick Bowler <nbowler@draconx.ca>
In-Reply-To: <20240529052543.GL2118490@ZenIV>
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On 2024-05-29 01:25, Al Viro wrote:
> On Wed, May 29, 2024 at 12:45:56AM -0400, Nick Bowler quoted:
> 
>>        All other headers use _IOC() macros to describe ioctls for a long time
>>        now. This header is stuck in the last century.
>>    
>>        Simply use the _IO() macro. No other changes.
> 
> ... are needed, since _IO() is arch-dependent; this is quite enough to fuck
> alpha and sparc over.  _IO(x,y) is (1<<29) + 256*x + y there; both ports
> got started with compat userland support, so _IO...() family there is
> modelled after OSF/1 and Solaris resp.
>
> kbd ioctls predate all of that.
> 
> Please, revert 8c467f330059 - commit in question breaks userland on alpha
> and on sparc for no reason whatsoever.  Might be worth adding a comment
> to those definitions at some point, but that can go on top of revert.

FWIW I see exactly the same problem with 6.10-rc1 on powerpc too.

> Folks, 0xXYZW is *not* an uncool way to spell _IO(0xXY,0xZW) - if there's
> any chance that those definitions are seen on all architectures, they
> should be left alone.

Thanks,
  Nick