Re: [PATCH bpf-next v2 1/2] bpf: Eliminate dup/restore of insn_aux_data
"Kumar Kartikeya Dwivedi" <[email protected]>
| Newsgroups | org.kernel.vger.bpf,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
On Mon Aug 10, 2026 at 11:17 PM CEST, Eduard Zingerman wrote: > On Tue, 2026-07-28 at 20:25 +0000, Xu Kuohai wrote: >> From: Xu Kuohai <[email protected]> >> >> The dup/restore of insn_aux_data was introduced to resolve the >> inconsistency between insnsi and insn_aux_data arrays, which occurs >> on the failure path where insnsi was rolled back to the original >> state before constants blinding, while insn_aux_data was not. >> >> After JIT failure, there is only one user, bpf_clear_insn_aux_data(), >> that requires insnsi and insn_aux_data to be synchronized. It accesses >> both insnsi and insn_aux_data using the same array size and index. >> >> However, the access to insnsi in bpf_clear_insn_aux_data() is not >> necessary. It is checked to skip the second slot of an ldimm64 instruction, >> whose jt is never set and can be absorbed into the jt check itself. >> >> So remove the access to insnsi from bpf_clear_insn_aux_data(), and add a >> specific length field for insn_aux_data to allow it to have a different >> length from the insnsi array. Then remove dup/restore of insn_aux_data. >> >> Signed-off-by: Xu Kuohai <[email protected]> >> --- > > Hi Xu, sorry for the delayed response, the patch lgtm. > > Acked-by: Eduard Zingerman <[email protected]> > > ... I applied this one for now, thanks.