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From: Alfred Perlstein <bright@mu.org>
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To: Konstantin Belousov <kostikbel@gmail.com>
Subject: Re: Fast sigblock (AKA rtld speedup)
References: <20130107182235.GA65279@kib.kiev.ua>
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On 1/7/13 1:22 PM, Konstantin Belousov wrote:
> Below is the forward of the patch for which I failed to obtain a private
> review. Might be, the list generates more responses.
Very cool.

Sorry for being rusty here, but is it safe to call fuword in the middle 
of issignal()?

The reason I ask is because it looks like proc lock is required for this 
block, and I forget it fuword(9) can fault.

If fuword(9) can fault then I don't think you can do this.

You'll need to use something like fuswintr(9) or wire the page down 
using vslock(9) or something.

I am probably missing something?

-Alfred