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Date:   Thu, 31 Mar 2022 14:33:22 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Heiko =?iso-8859-1?Q?St=FCbner?= <heiko@sntech.de>
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Subject: Re: [PATCH v8 01/14] riscv: prevent null-pointer dereference with
 sbi_remote_fence_i
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References: <20220324000710.575331-1-heiko@sntech.de> <20220324000710.575331-2-heiko@sntech.de> <20220331095155.GA23422@lst.de> <2260961.n0HT0TaD9V@diego>
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On Thu, Mar 31, 2022 at 02:28:06PM +0200, Heiko St?bner wrote:
> so essentially flushes the _local_ icache first and then tries to flush
> caches on other cores, either via an ipi or via sbi.
> 
> The remote-fence callback is set correctly during sbi_init().
> The other cores are only brought up after sbi-init is done.
> 
> So it's not really about error reporting but making sure that flush_icache_all()
> does something sane even when still running on the first core.
> As I assume the "all" means on all available cores (which would be the
> core the system booted on).
> 
> Does this make it clearer what this tries to solve?

A little.  Whatever code calls this early still seems broken to me
and just just do a local flush, though.