From: David Vrabel <david.vrabel@citrix.com>
To: Wei Liu <wei.liu2@citrix.com>,
Xen-devel <xen-devel@lists.xenproject.org>
Cc: Ian Jackson <Ian.Jackson@eu.citrix.com>
Subject: Re: [PATCH 1/2] libs/gnttab: do not use alloca(3)
Date: Mon, 22 Aug 2016 10:46:50 +0100 [thread overview]
Message-ID: <57BACA0A.6050807@citrix.com> (raw)
In-Reply-To: <1471444382-30409-2-git-send-email-wei.liu2@citrix.com>
On 17/08/16 15:33, Wei Liu wrote:
> The semantics of alloca(3) is not very nice. If the stack overflows,
> program behaviour is undefined.
>
> Remove the use of alloca(3) and always use mmap.
This is only using alloca() if the allocation is < PAGE_SIZE. I think
assuming there's this much extra stack is fine.
Using alloca() avoids the (expensive) mmap() system call.
David
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next prev parent reply other threads:[~2016-08-22 9:47 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-08-17 14:33 [PATCH 0/2] tools/libs: don't use alloca(3) Wei Liu
2016-08-17 14:33 ` [PATCH 1/2] libs/gnttab: do not " Wei Liu
2016-08-22 9:46 ` David Vrabel [this message]
2016-08-22 10:10 ` Wei Liu
2016-08-22 10:24 ` David Vrabel
2016-08-22 10:44 ` Wei Liu
2016-08-17 14:33 ` [PATCH 2/2] libs/foreignmemory: " Wei Liu
2016-08-17 23:39 ` [PATCH 0/2] tools/libs: don't " Dario Faggioli
2016-08-18 9:29 ` Wei Liu
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