Date: Wed, 19 Nov 2014 16:59:48 +0000
From: Russell King - ARM Linux <linux@arm.linux.org.uk>
To: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        Konstantin Khlebnikov <koct9i@gmail.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Andrey Ryabinin <a.ryabinin@samsung.com>,
        Konstantin Khlebnikov <k.khlebnikov@samsung.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH RFC] ARM: option for loading modules into vmalloc area
Message-ID: <20141119165948.GM4042@n2100.arm.linux.org.uk>
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On Wed, Nov 19, 2014 at 11:57:15AM -0500, Nicolas Pitre wrote:
> On Wed, 19 Nov 2014, Russell King - ARM Linux wrote:
> > I don't think I ever did, because its pretty much impossible to do as I
> > explained in a follow up to this thread.
> > 
> > We _used_ to do this with the userspace insmod methods, but since we got
> > this kernel-side linker, it's been pretty much impossible to do without
> > rewriting the module code.  That's not going to happen on account of one
> > quirky architecture which Linus doesn't particularly like.
> 
> Still... We could try adding a hook in the generic module linker code 
> for a pre-relocation pass.  Maybe only ARM would use it, but if the need 
> to load big modules is real then I imagine Linus could be amenable to a 
> compromise.

So, how big a table would you allocate for the trampolines, based upon
not knowing anything about the module being loaded?  4K?  8K?  64K?

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