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Miller" , "David Ahern" , "Thomas Gleixner" , "Ingo Molnar" , "Borislav Petkov" , "Dave Hansen" , "X86 ML" , "H. Peter Anvin" , "Shuah Khan" , "Maxime Coquelin" , "Alexandre Torgue" , "Andrey Ryabinin" , "Alexander Potapenko" , "Dmitry Vyukov" , "Vincenzo Frascino" , "Andrew Morton" , , "Bastien Curutchet" , "Thomas Petazzoni" , "Xu Kuohai" , "bpf" , "LKML" , "Network Development" , "open list:KERNEL SELFTEST FRAMEWORK" , , "linux-arm-kernel" , "kasan-dev" , "linux-mm" From: =?utf-8?q?Alexis_Lothor=C3=A9?= To: "Alexei Starovoitov" , =?utf-8?q?Alexis_Lothor=C3=A9?= X-Mailer: aerc 0.21.0-0-g5549850facc2 References: <20260413-kasan-v1-0-1a5831230821@bootlin.com> <20260413-kasan-v1-1-1a5831230821@bootlin.com> In-Reply-To: X-Last-TLS-Session-Version: TLSv1.3 X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 233BC140019 X-Stat-Signature: zzzr3qm8zdjuxaxm33rup16t3u4yo8fw X-Rspam-User: X-HE-Tag: 1776192119-735428 X-HE-Meta: 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 ljtTrN83 SWFn6Z7crUdvLYQJ/rL95W06d/AFU7cKiOcOuD+WqPosVxRvzrMppnbJDSu3PBLxS0z1zUxIud5e0Xu7w7E3NG5gCuucuxTudISQEECXVtKcU6nTdDbRXUaPiqM2dGYyKzFPxn1qG0tvI3SDB5L6mkLstn6hRO2RenGlJ7PdiBbUMPvsOoup3aajWwWAyPiQaP/6aI+G1rJxnUy2jIA9VhQELcbW/5KzR3IV7x27BlZbT0BlB9MLhgnai0BwfPFMIobqt1cVX7I0nNRV4ObwvQtXtlpxXCBMDPhkJqUSlVh/xLtHk7vMfc380+Re7h5+Fz7L4iNDIHdKUSc6UcmTKhOpNY77yAnbTaQWxLlzvrY2FZSX86RGZKItphINaEvDJAT1k4DUrmL0VokBoilH88OmZEM0/cKAxKwfxI5wheK/LuIesGZZyCZf+9EVgxMIL/v2Q Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue Apr 14, 2026 at 4:36 PM CEST, Alexei Starovoitov wrote: > On Tue, Apr 14, 2026 at 6:13=E2=80=AFAM Alexis Lothor=C3=A9 > wrote: >> >> Hi Andrey, thanks for the prompt review ! >> >> On Tue Apr 14, 2026 at 12:19 AM CEST, Andrey Konovalov wrote: >> > On Mon, Apr 13, 2026 at 8:29=E2=80=AFPM Alexis Lothor=C3=A9 (eBPF Foun= dation) >> > wrote: >> >> >> >> [...] >> >> >> +#ifdef CONFIG_KASAN_GENERIC >> >> +void __asan_load1(void *p); >> >> +void __asan_store1(void *p); >> >> +void __asan_load2(void *p); >> >> +void __asan_store2(void *p); >> >> +void __asan_load4(void *p); >> >> +void __asan_store4(void *p); >> >> +void __asan_load8(void *p); >> >> +void __asan_store8(void *p); >> >> +void __asan_load16(void *p); >> >> +void __asan_store16(void *p); >> >> +#endif /* CONFIG_KASAN_GENERIC */ >> > >> > This looks ugly, let's not do this unless it's really required. >> > >> > You can just use kasan_check_read/write() instead - these are public >> > wrappers around the same shadow memory checking functions. And they >> > also work with the SW_TAGS mode, in case the BPF would want to use >> > that mode at some point. (For HW_TAGS, we only have kasan_check_byte() >> > that checks a single byte, but it can be extended in the future if >> > required to be used by BPF.) >> >> ACK, I'll try to use those kasan_check_read and kasan_check_write rather >> than __asan_{load,store}X. > > No. The performance penalty will be too high. Since we are mentioning it, I did not consider yet any performance comparision/benchmarking (and I am not really familiar with usual bpf performance validation practices for new bpf features). Is there any existing test I should take a look at for this ? Maybe some specific benches in tools/testing/selftests/bpf/bench ?=20 > hw_tags won't work without corresponding JIT work. > I see no point sacrificing performance for aesthetics. > __asan_load/storeX is what compilers emit. > In that sense JIT is a compiler it should emit exactly the same. --=20 Alexis Lothor=C3=A9, Bootlin Embedded Linux and Kernel engineering https://bootlin.com