Re: [PATCHv2 1/3] EDAC/altera: Use fast register IO for S10 IRQs

From: Borislav Petkov
Date: Fri Nov 22 2019 - 04:03:20 EST


On Thu, Nov 21, 2019 at 12:30:46PM -0600, thor.thayer@xxxxxxxxxxxxxxx wrote:
> From: Meng Li <Meng.Li@xxxxxxxxxxxxx>
>
> When an irq occurs in altera edac driver, regmap_xxx() is invoked
> in atomic context. Regmap must indicate register IO is fast so
> that a spinlock is used instead of a mutex to avoid sleeping
> in atomic context.
>
> Fixes mutex-lock error
> lock_acquire+0xfc/0x288
> __mutex_lock+0x8c/0x808
> mutex_lock_nested+0x3c/0x50
> regmap_lock_mutex+0x24/0x30
> regmap_write+0x40/0x78
> a10_eccmgr_irq_unmask+0x34/0x40
> unmask_irq.part.0+0x30/0x50
> irq_enable+0x74/0x80
> __irq_startup+0x80/0xa8
> irq_startup+0x70/0x150
> __setup_irq+0x650/0x6d0
> request_threaded_irq+0xe4/0x180
> devm_request_threaded_irq+0x7c/0xf0
> altr_sdram_probe+0x2c4/0x600
> <snip>
>
> Upstream fix pending [1] (common code uses fast mode)
> [1] https://lkml.org/lkml/2019/11/7/1014
>
> Fixes: 3dab6bd52687 ("EDAC, altera: Add support for Stratix10 SDRAM EDAC")
> Cc: stable@xxxxxxxxxxxxxxx
> Reported-by: Meng Li <Meng.Li@xxxxxxxxxxxxx>
> Signed-off-by: Meng Li <Meng.Li@xxxxxxxxxxxxx>
> Reviewed-by: Thor Thayer <thor.thayer@xxxxxxxxxxxxxxx>
> ---
> v2 Change Author to Meng Li & Reviewed-by: Thor Thayer

You don't absolutely need to have Reviewed-by: you, when you send
someone else's patch. The fact that you send it, kinda implies you've
reviewed it. I sure hope so, at least :-)

What the patch must have is your SOB unterneath. I'll fix that up when
applying.

Thx.

--
Regards/Gruss,
Boris.

https://people.kernel.org/tglx/notes-about-netiquette