Re: [PATCH v2 2/2] MIPS: relocatable: Use __kaslr_offset in show_kernel_relocation

[Jinyang He]

On 02/04/2021 11:36 PM, Thomas Bogendoerfer wrote:

> On Wed, Feb 03, 2021 at 06:35:10PM +0800, Jinyang He wrote:
> > The type of the VMLINUX_LOAD_ADDRESS macro is the (unsigned long long)
> > in 32bits kernel but (unsigned long) in the 64-bit kernel. Although there
> > is no error here, avoid using it to calculate kaslr_offset. And here we
> > may need is that the address of __kaslr_offset rather than (void *)offset.
> >
> > Signed-off-by: Jinyang He <hejinyang@xxxxxxxxxxx>
> > ---
> >   arch/mips/kernel/relocate.c | 8 ++------
> >   1 file changed, 2 insertions(+), 6 deletions(-)
> >
> > diff --git a/arch/mips/kernel/relocate.c b/arch/mips/kernel/relocate.c
> > index 95abb9c..52018a3 100644
> > --- a/arch/mips/kernel/relocate.c
> > +++ b/arch/mips/kernel/relocate.c
> > @@ -430,13 +430,9 @@ void *__init relocate_kernel(void)
> >    */
> >   static void show_kernel_relocation(const char *level)
> >   {
> > -	unsigned long offset;
> > -
> > -	offset = __pa_symbol(_text) - __pa_symbol(VMLINUX_LOAD_ADDRESS);
> > -
> > -	if (IS_ENABLED(CONFIG_RELOCATABLE) && offset > 0) {
> > +	if (__kaslr_offset > 0) {
> >   		printk(level);
> > -		pr_cont("Kernel relocated by 0x%pK\n", (void *)offset);
> > +		pr_cont("Kernel relocated by 0x%pK\n", &__kaslr_offset);
> are you sure ? I would have expected (void *)__kaslr_offset here.
>
> Thomas.
It is my fault. I misunderstood the meaning of 'by' and '@' because of
my poor English. Thank you for pointing out my fault. I'll send v3 later.

Thanks,
Jinyang