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Date: Mon, 5 Jun 2017 16:51:49 +1000
From: Nicholas Piggin <npiggin@gmail.com>
To: Balbir Singh <bsingharora@gmail.com>
Cc: "open list:LINUX FOR POWERPC (32-BIT AND 64-BIT)"
 <linuxppc-dev@lists.ozlabs.org>, Michael Ellerman <mpe@ellerman.id.au>,
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 <naveen.n.rao@linux.vnet.ibm.com>, Laura Abbott <labbott@redhat.com>,
 Rashmica Gupta <rashmica.g@gmail.com>
Subject: Re: [PATCH v2 5/9] powerpc/vmlinux.lds: Align __init_begin to 16M
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On Mon, 5 Jun 2017 08:42:40 +1000
Balbir Singh <bsingharora@gmail.com> wrote:

> On Sun, Jun 4, 2017 at 2:22 PM, Nicholas Piggin <npiggin@gmail.com> wrote:
> > On Sat,  3 Jun 2017 17:18:39 +1000
> > Balbir Singh <bsingharora@gmail.com> wrote:
> >  
> >> For CONFIG_STRICT_KERNEL_RWX align __init_begin to 16M.
> >> We use 16M since its the larger of 2M on radix and 16M
> >> on hash for our linear mapping. The plan is to have
> >> .text, .rodata and everything upto __init_begin marked
> >> as RX. Note we still have executable read only data.
> >> We could further align read only data to another 16M
> >> boundary, but then the linker starts using stubs and
> >> that breaks our assembler code in head_64.S  
> >
> > Is this still the case with powerpc next?
> >  
> 
> Sorry, no, I was on linux-next for testing, but I think your linker
> stub patches went in very recently. I'll rebase on top and test,

That would be good. I'd like to make sure the linker stub workaround
does work for your case.

> but I am not sure if I want two 16M alignments and bloat the size
> of vmlinux. But I'll double check what happens

Maybe it could be an option.

Thanks,
Nick