Re: [PATCH] ARM: kexec: Fix panic after TLB are invalidated

[Giancarlo Ferrari]

Hi all,

On Tue, Jan 12, 2021 at 04:49:06PM +0000, Giancarlo Ferrari wrote:
> machine_kexec() need to set rw permission in text and rodata sections
> to assign some variables (e.g. kexec_start_address). To do that at
> the end (after flushing pdm in memory, inv D-Cache, etc.) it needs to
> invalidate TLB [section] entries.
> 
> If during the TLB invalidation an interrupt occours, which might cause
> a context switch, there is the risk to inject invalid TLBs, with ro
> permissions.
> 
> When trying to assign .text labels, this lead to the following issue:
> 
> "Unable to handle kernel paging request at virtual address <valid_addr>"
> 
> with FSR 0x80d.
> 
> Signed-off-by: Giancarlo Ferrari <giancarlo.ferrari89@xxxxxxxxx>
> ---
>  arch/arm/kernel/machine_kexec.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)

has been re-submitted here:

https://lore.kernel.org/lkml/1612140296-12546-1-git-send-email-giancarlo.ferrari89@xxxxxxxxx/


GF