Re: [PATCH RESEND v8 11/16] powerpc: extend execmem_params for kprobes allocations

[Mike Rapoport]

Hi Christophe,

On Fri, Nov 13, 2026 at 03:36:01PM +0100, Christophe Leroy (CS GROUP) wrote:
> Hi Mike,
> 
> Looks like I missed this change ...
> 
> Le 05/05/2024 à 18:06, Mike Rapoport a écrit :
> > From: "Mike Rapoport (IBM)" <rppt@xxxxxxxxxx>
> > 
> > powerpc overrides kprobes::alloc_insn_page() to remove writable
> > permissions when STRICT_MODULE_RWX is on.
> > 
> > Add definition of EXECMEM_KRPOBES to execmem_params to allow using the
> > generic kprobes::alloc_insn_page() with the desired permissions.
> > 
> > As powerpc uses breakpoint instructions to inject kprobes, it does not
> > need to constrain kprobe allocations to the modules area and can use the
> > entire vmalloc address space.
> 
> Using breakpoint means the segment must still be executable.
> On book3s/32 VMALLOC segment is not executable, while module segment is.
> 
> See commit 6ca055322da8 ("powerpc/32s: Use dedicated segment for modules
> with STRICT_KERNEL_RWX")
> 
> See report and fix at https://lore.kernel.org/all/ed03d290d440d579a81ae0b7de5243721291d903.1794543909.git.ritesh.list@xxxxxxxxx/

I'll take a look, thanks!
 
> Christophe

-- 
Sincerely yours,
Mike.