Re: [PATCH bpf-next v7 4/5] bpf: verifier: Support eliding map lookup nullness

2025-02-01 Thread Daniel Xu
On Thu, Jan 30, 2025, at 7:41 PM, Daniel Xu wrote: > Hi Ilya, > > On Thu, Jan 30, 2025, at 2:06 AM, Ilya Leoshkevich wrote: >> On Wed, 2025-01-29 at 10:45 -0700, Daniel Xu wrote: >>> On Wed, Jan 29, 2025 at 09:49:12AM -0700, Daniel Xu wrote: >>> > Hi Ilya, >>> > >>> > On Wed, Jan 29, 2025 at 03

Re: [PATCH bpf-next v7 4/5] bpf: verifier: Support eliding map lookup nullness

2025-01-30 Thread Daniel Xu
Hi Ilya, On Thu, Jan 30, 2025, at 2:06 AM, Ilya Leoshkevich wrote: > On Wed, 2025-01-29 at 10:45 -0700, Daniel Xu wrote: >> On Wed, Jan 29, 2025 at 09:49:12AM -0700, Daniel Xu wrote: >> > Hi Ilya, >> > >> > On Wed, Jan 29, 2025 at 03:58:54PM +0100, Ilya Leoshkevich wrote: >> > > On Tue, 2025-01-1

Re: [PATCH bpf-next v7 4/5] bpf: verifier: Support eliding map lookup nullness

2025-01-30 Thread Marc Hartmayer
On Wed, Jan 29, 2025 at 10:45 AM -0700, Daniel Xu wrote: > On Wed, Jan 29, 2025 at 09:49:12AM -0700, Daniel Xu wrote: >> Hi Ilya, >> […snip…] > > I cribbed the source from [0] and tested before and after. I think this > should work. Mind giving it a try? Hi Daniel, thanks for the fix! I’ve te

Re: [PATCH bpf-next v7 4/5] bpf: verifier: Support eliding map lookup nullness

2025-01-30 Thread Ilya Leoshkevich
On Wed, 2025-01-29 at 10:45 -0700, Daniel Xu wrote: > On Wed, Jan 29, 2025 at 09:49:12AM -0700, Daniel Xu wrote: > > Hi Ilya, > > > > On Wed, Jan 29, 2025 at 03:58:54PM +0100, Ilya Leoshkevich wrote: > > > On Tue, 2025-01-14 at 13:28 -0700, Daniel Xu wrote: > > > > This commit allows progs to elid

Re: [PATCH bpf-next v7 4/5] bpf: verifier: Support eliding map lookup nullness

2025-01-29 Thread Daniel Xu
On Wed, Jan 29, 2025 at 09:49:12AM -0700, Daniel Xu wrote: > Hi Ilya, > > On Wed, Jan 29, 2025 at 03:58:54PM +0100, Ilya Leoshkevich wrote: > > On Tue, 2025-01-14 at 13:28 -0700, Daniel Xu wrote: > > > This commit allows progs to elide a null check on statically known > > > map > > > lookup keys.

Re: [PATCH bpf-next v7 4/5] bpf: verifier: Support eliding map lookup nullness

2025-01-29 Thread Daniel Xu
Hi Ilya, On Wed, Jan 29, 2025 at 03:58:54PM +0100, Ilya Leoshkevich wrote: > On Tue, 2025-01-14 at 13:28 -0700, Daniel Xu wrote: > > This commit allows progs to elide a null check on statically known > > map > > lookup keys. In other words, if the verifier can statically prove > > that > > the loo

Re: [PATCH bpf-next v7 4/5] bpf: verifier: Support eliding map lookup nullness

2025-01-29 Thread Ilya Leoshkevich
On Tue, 2025-01-14 at 13:28 -0700, Daniel Xu wrote: > This commit allows progs to elide a null check on statically known > map > lookup keys. In other words, if the verifier can statically prove > that > the lookup will be in-bounds, allow the prog to drop the null check. > > This is useful for tw