Naveen N. Rao 3bfbc00587 powerpc64/bpf: Limit 'ldbrx' to processors compliant with ISA v2.06 ... [ Upstream commit 3f5f766d5f ] Johan reported the below crash with test_bpf on ppc64 e5500: test_bpf: #296 ALU_END_FROM_LE 64: 0x0123456789abcdef -> 0x67452301 jited:1 Oops: Exception in kernel mode, sig: 4 [#1] BE PAGE_SIZE=4K SMP NR_CPUS=24 QEMU e500 Modules linked in: test_bpf(+) CPU: 0 PID: 76 Comm: insmod Not tainted 5.14.0-03771-g98c2059e008a-dirty #1 NIP: 8000000000061c3c LR: 80000000006dea64 CTR: 8000000000061c18 REGS: c0000000032d3420 TRAP: 0700 Not tainted (5.14.0-03771-g98c2059e008a-dirty) MSR: 0000000080089000 <EE,ME> CR: 88002822 XER: 20000000 IRQMASK: 0 <...> NIP [8000000000061c3c] 0x8000000000061c3c LR [80000000006dea64] .__run_one+0x104/0x17c [test_bpf] Call Trace: .__run_one+0x60/0x17c [test_bpf] (unreliable) .test_bpf_init+0x6a8/0xdc8 [test_bpf] .do_one_initcall+0x6c/0x28c .do_init_module+0x68/0x28c .load_module+0x2460/0x2abc .__do_sys_init_module+0x120/0x18c .system_call_exception+0x110/0x1b8 system_call_common+0xf0/0x210 --- interrupt: c00 at 0x101d0acc <...> ---[ end trace 47b2bf19090bb3d0 ]--- Illegal instruction The illegal instruction turned out to be 'ldbrx' emitted for BPF_FROM_[L|B]E, which was only introduced in ISA v2.06. Guard use of the same and implement an alternative approach for older processors. Fixes: 156d0e290e ("powerpc/ebpf/jit: Implement JIT compiler for extended BPF") Reported-by: Johan Almbladh <johan.almbladh@anyfinetworks.com> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Tested-by: Johan Almbladh <johan.almbladh@anyfinetworks.com> Acked-by: Johan Almbladh <johan.almbladh@anyfinetworks.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/d1e51c6fdf572062cf3009a751c3406bda01b832.1641468127.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>		2022-02-01 17:27:09 +01:00
..
bpf_jit64.h	powerpc/bpf: Emit stf barrier instruction sequences for BPF_NOSPEC	2021-10-07 19:52:58 +11:00
bpf_jit_comp32.c	powerpc/bpf: Update ldimm64 instructions during extra pass	2022-02-01 17:27:00 +01:00
bpf_jit_comp64.c	powerpc64/bpf: Limit 'ldbrx' to processors compliant with ISA v2.06	2022-02-01 17:27:09 +01:00
bpf_jit_comp.c	powerpc/bpf: Update ldimm64 instructions during extra pass	2022-02-01 17:27:00 +01:00
bpf_jit.h	powerpc/bpf: Validate branch ranges	2021-10-07 18:52:33 +11:00
Makefile	powerpc/bpf: Implement extended BPF on PPC32	2021-04-03 21:22:21 +11:00