Re: alpha: potential race around hae_cache in RESTORE_ALL

[Linus Torvalds]

On Mon, Sep 27, 2010 at 9:26 AM, Ivan Kokshaysky
<ink@xxxxxxxxxxxxxxxxxxxx> wrote:
>
> Looks like we need to drop HAE bits from SAVE_ALL/RESTORE_ALL, which
> benefits (1) and automatically fixes (3), and do the entire IO sequences
> in (2) with disabled interrupts (if HAE is involved).

No can do.

HAE is used in user space too (the X server), and it depends on the
kernel restoring HAE over interrupts and system calls, afaik.

I'm also pretty certain that all SMP machines either don't have HAE at
all, or have a per-CPU HAE in hardware (and then it's possible that we
screw it up in software, of course). Anything else would be too broken
for words. Can somebody find documentation saying otherwise?

                        Linus
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