Re: [PATCH] arm64: vmlinux.lds.S: keep .entry.tramp.text section

From: Catalin Marinas
Date: Tue Mar 16 2021 - 06:46:27 EST


On Fri, Feb 26, 2021 at 08:32:57PM -0800, Fangrui Song wrote:
> On 2021-02-26, Kees Cook wrote:
> > On Fri, Feb 26, 2021 at 03:03:39PM +0100, Arnd Bergmann wrote:
> > > From: Arnd Bergmann <arnd@xxxxxxxx>
> > >
> > > When building with CONFIG_LD_DEAD_CODE_DATA_ELIMINATION,
> > > I sometimes see an assertion
> > >
> > > ld.lld: error: Entry trampoline text too big
> >
> > Heh, "too big" seems a weird report for having it discarded. :)
> >
> > Any idea on this Fangrui?
> >
> > ( I see this is https://github.com/ClangBuiltLinux/linux/issues/1311 )
>
> This diagnostic is from an ASSERT in arch/arm64/kernel/vmlinux.lds
>
> ASSERT((__entry_tramp_text_end - __entry_tramp_text_start) == (1 << 16),
> "Entry trampoline text too big")

Can we not change the ASSERT to be <= PAGE_SIZE instead?

--
Catalin