On 2016/06/22 08:37PM, Michael Ellerman wrote: > On Tue, 2016-06-07 at 19:02 +0530, Naveen N. Rao wrote: > > > PPC64 eBPF JIT compiler. > > > > Enable with: > > echo 1 > /proc/sys/net/core/bpf_jit_enable > > or > > echo 2 > /proc/sys/net/core/bpf_jit_enable > > > > ... to see the generated JIT code. This can further be processed with > > tools/net/bpf_jit_disasm. > > > > With CONFIG_TEST_BPF=m and 'modprobe test_bpf': > > test_bpf: Summary: 305 PASSED, 0 FAILED, [297/297 JIT'ed] > > > > ... on both ppc64 BE and LE. > > > > The details of the approach are documented through various comments in > > the code. > > This is crashing for me on a Cell machine, not sure why at a glance: > > > test_bpf: #250 JMP_JSET_X: if (0x3 & 0xffffffff) return 1 jited:1 14 PASS > test_bpf: #251 JMP_JA: Jump, gap, jump, ... jited:1 15 PASS > test_bpf: #252 BPF_MAXINSNS: Maximum possible literals > Unable to handle kernel paging request for data at address 0xd000000007b20000 > Faulting instruction address: 0xc000000000667b6c > cpu 0x0: Vector: 300 (Data Access) at [c0000007f83bf3a0] > pc: c000000000667b6c: .flush_icache_range+0x3c/0x84 > lr: c000000000082354: .bpf_int_jit_compile+0x1fc/0x2c8 > sp: c0000007f83bf620 > msr: 900000000200b032 > dar: d000000007b20000 > dsisr: 40000000 > current = 0xc0000007f8249580 > paca = 0xc00000000fff0000 softe: 0 irq_happened: 0x01 > pid = 1822, comm = insmod > Linux version 4.7.0-rc3-00061-g007c99b9d8c1 (mich...@ka3.ozlabs.ibm.com) (gcc > version 6.1.0 (GCC) ) #3 SMP Wed Jun 22 19:22:23 AEST 2016 > enter ? for help > [link register ] c000000000082354 .bpf_int_jit_compile+0x1fc/0x2c8 > [c0000007f83bf620] c0000000000822fc .bpf_int_jit_compile+0x1a4/0x2c8 > (unreliable) > [c0000007f83bf700] c00000000013cda4 .bpf_prog_select_runtime+0x24/0x108 > [c0000007f83bf780] c000000000548918 .bpf_prepare_filter+0x9b0/0x9e8 > [c0000007f83bf830] c0000000005489d4 .bpf_prog_create+0x84/0xd0 > [c0000007f83bf8c0] d000000003b21158 .test_bpf_init+0x28c/0x83c [test_bpf] > [c0000007f83bfa00] c00000000000a7b4 .do_one_initcall+0x5c/0x1c0 > [c0000007f83bfae0] c000000000669058 .do_init_module+0x80/0x21c > [c0000007f83bfb80] c00000000011e3a0 .load_module+0x2028/0x23a8 > [c0000007f83bfd20] c00000000011e898 .SyS_init_module+0x178/0x1b0 > [c0000007f83bfe30] c000000000009220 system_call+0x38/0x110 > --- Exception: c01 (System Call) at 000000000ff5e0c4 > SP (ffde0960) is in userspace > 0:mon> r > R00 = 000000000000c01c R16 = 0000000000000000 > R01 = c0000007f83bf620 R17 = 00000000024000c0 > R02 = c00000000094ce00 R18 = 0000000000000000 > R03 = d000000007b10000 R19 = d000000003c32df0 > R04 = d000000007b40338 R20 = c00000000072b488
Wow. I can't actually understand why this did not trigger for me. We are sending incorrect values into flush_icache_range(). So the first page is being flushed properly, but we are faulting trying to access another page. Patch forthcoming. Thanks, Naveen _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
