Re: [PATCH] MIPS: Ignore relocs against __ex_table for relocatable kernel

From: Thomas Bogendoerfer
Date: Wed Feb 26 2025 - 14:37:43 EST


On Wed, Feb 26, 2025 at 10:43:40AM -0500, Steven Rostedt wrote:
> On Wed, 26 Feb 2025 21:28:41 +0800
> Xi Ruoyao <xry111@xxxxxxxxxxx> wrote:
>
> > Since commit 6f2c2f93a190 ("scripts/sorttable: Remove unneeded
> > Elf_Rel"), sorttable no longer clears relocs against __ex_table,
> > claiming "it was never used." But in fact MIPS relocatable kernel had
> > been implicitly depending on this behavior, so after this commit the
> > MIPS relocatable kernel has started to spit oops like:
>
> Oops!
>
> >
> > CPU 1 Unable to handle kernel paging request at virtual address 000000fffbbdbff8, epc == ffffffff818f9a6c, ra == ffffffff813ad7d0
> > ... ...
> > Call Trace:
> > [<ffffffff818f9a6c>] __raw_copy_from_user+0x48/0x2fc
> > [<ffffffff813ad7d0>] cp_statx+0x1a0/0x1e0
> > [<ffffffff813ae528>] do_statx_fd+0xa8/0x118
> > [<ffffffff813ae670>] sys_statx+0xd8/0xf8
> > [<ffffffff81156cc8>] syscall_common+0x34/0x58
> >
> > So ignore those relocs on our own to fix the issue.
> >
> > Fixes: 6f2c2f93a190 ("scripts/sorttable: Remove unneeded Elf_Rel")
> > Signed-off-by: Xi Ruoyao <xry111@xxxxxxxxxxx>
>
> Thanks! Yeah, this is better than having an implicit dependency to the
> sorttable code.
>
> I take it that this will go through the mips tree?

yes, I'll take it.

Thomas.

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