Re: [PATCH bpf-next v3 03/10] bpf: add BPF_JIT_KASAN for KASAN instrumentation of JITed programs

[Alexis Lothoré]

Hi Andrey,

On Wed Jul 1, 2026 at 3:43 PM CEST, Andrey Konovalov wrote:
> On Wed, Jul 1, 2026 at 12:03 PM Alexis Lothoré (eBPF Foundation)
> <alexis.lothore@xxxxxxxxxxx> wrote:

[...]

>> +config BPF_JIT_KASAN
>> +       bool
>> +       depends on HAVE_EBPF_JIT_KASAN
>> +       default y if BPF_JIT && KASAN_GENERIC && KASAN_VMALLOC && VMAP_STACK
>
> I think it make sense to put KASAN_GENERIC into the "depends on"
> section, as __asan_load/storeX() are only defined for the Generic
> mode. SW_TAGS mode is expected to be soon implemented for x86-64, and
> that mode uses different checking function names.

I guess I can move most of the kconfig options that currently are in the
`default y if ...` into dedicated `depends on ...` lines, and just keep
a `default y if KASAN`, something like:

  config BPF_JIT_KASAN
          bool
          depends on HAVE_EBPF_JIT_KASAN
          depends on KASAN_GENERIC
          depends on KASAN_VMALLOC
          depends on VMAP_STACK
          depends on BPF_JIT
          default y if KASAN

> Would also be great to add description for this config option.

I can fill a help field with a basic description, but it will be visible
only by reading the Kconfig file, it will not appear in menuconfig
unless we make the knob user-selectable, which I would like to avoid.

Thanks,

Alexis

-- 
Alexis Lothoré, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com