On Thu, Jun 18, 2020 at 10:55:58AM +0200, David Hildenbrand wrote: > On 18.06.20 08:43, Christoph Hellwig wrote: > > Use PAGE_KERNEL_ROX directly instead of allocating RWX and setting the > > page read-only just after the allocation. > > > > Signed-off-by: Christoph Hellwig <[email protected]> > > --- > > arch/arm64/kernel/probes/kprobes.c | 12 +++--------- > > 1 file changed, 3 insertions(+), 9 deletions(-) > > > > diff --git a/arch/arm64/kernel/probes/kprobes.c > > b/arch/arm64/kernel/probes/kprobes.c > > index d1c95dcf1d7833..cbe49cd117cfec 100644 > > --- a/arch/arm64/kernel/probes/kprobes.c > > +++ b/arch/arm64/kernel/probes/kprobes.c > > @@ -120,15 +120,9 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) > > > > void *alloc_insn_page(void) > > { > > - void *page; > > - > > - page = vmalloc_exec(PAGE_SIZE); > > - if (page) { > > - set_memory_ro((unsigned long)page, 1); > > - set_vm_flush_reset_perms(page); > > - } > > - > > - return page; > > + return __vmalloc_node_range(PAGE_SIZE, 1, VMALLOC_START, VMALLOC_END, > > + GFP_KERNEL, PAGE_KERNEL_ROX, VM_FLUSH_RESET_PERMS, > > + NUMA_NO_NODE, __func__); > > I do wonder if something like vmalloc_prot(size, prot) would make this > (and the other two users) easier to read. > > So instead of ripping out vmalloc_exec(), converting it into > vmalloc_prot() instead. > > Did you consider that?
For x86 Christoph did module_alloc_prot(), which is in his more extensive set of patches addressing this. I suspect that would be the right thing for ARM64 as well.
