On Tue, Nov 15, 2022 at 09:48:27AM +0800, Hao Sun wrote: SNIP > > > > Hi Jirka, > > > > > > > > I've tested the proposed patch, the warning from bpf_bprintf_prepare will not > > > > be triggered with the patch, but the reproducer can still trigger the following > > > > warning. My test was conducted on: > > > > > > > > commit: f67dd6ce0723 Merge tag 'slab-for-6.1-rc4-fixes' > > > > git tree: upstream > > > > kernel config: https://pastebin.com/raw/sE5QK5HL > > > > C reproducer: https://pastebin.com/raw/X96ASi27 > > > > console log *before* the patch: https://pastebin.com/raw/eSCUNFrd > > > > console log *after* the patch: https://pastebin.com/raw/tzcmdWZt > > > > > > thanks for testing.. I can't reproduce this for some reason > > > > > > I'll check some more and perhaps go with denying bpf attachment > > > for this tracepoint as Alexei suggeste > > > > the change below won't allow to attach bpf program with any printk > > helper in contention_begin and bpf_trace_printk tracepoints > > > > I still need to test it on the machine that reproduced the issue > > for me.. meanwhile any feedback is appreciated > > > > Hi, > > Tested on my machine, the C reproducer won't trigger any issue > this time with the patch. The test was conducted on: > > commit: f67dd6ce0723 Merge tag 'slab-for-6.1-rc4-fixes' > git tree: upstream > kernel config: https://pastebin.com/raw/sE5QK5HL > C reproducer: https://pastebin.com/raw/X96ASi27 > full console log *before* the patch: https://pastebin.com/raw/n3x55RDr > full console log *after* the patch: https://pastebin.com/raw/7HdxnCnL thanks, looks good on my end as well jirka
