Date: Sun, 21 Mar 2004 16:28:38 -0800 (PST) From: Bill Paul <wpaul@FreeBSD.org> To: src-committers@FreeBSD.org, cvs-src@FreeBSD.org, cvs-all@FreeBSD.org Subject: cvs commit: src/sys/i386/i386 vm_machdep.c Message-ID: <200403220028.i2M0ScPc047763@repoman.freebsd.org>
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wpaul 2004/03/21 16:28:38 PST
FreeBSD src repository
Modified files:
sys/i386/i386 vm_machdep.c
Log:
The kthread_create() API is supposed to allow you to create threads
with more than the normal amount of stack pages, however the stack
pointer always wound up being initialized using KSTACK_PAGES. It
should be using td->td_kstack_pages instead. This means that although
the vm subsystem would give you all the stack pages you asked for,
%esp would always be initialized as if you had just 2 pages, and
the rest would go to waste.
I wanted to use the 'give me more stack pages' feature of kthread_create()
because the Intel 2200BG NDIS driver does an alloca() of about 5000 bytes,
which wrecks the stack with the default 2 page size, and I was baffled
that no matter how much code I shoved into thread contexts with
allegedly larger stacks, the thing would still crash unless I changed
KSTACK_PAGES.
Note: this bug is present in _ALL_ arches at this point. Peter has
promised to merge this fix into all of them.
Revision Changes Path
1.233 +4 -3 src/sys/i386/i386/vm_machdep.c
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