Tong Tiangen 252c765bd7 riscv, bpf: Add BPF exception tables ... When a tracing BPF program attempts to read memory without using the bpf_probe_read() helper, the verifier marks the load instruction with the BPF_PROBE_MEM flag. Since the riscv JIT does not currently recognize this flag it falls back to the interpreter. Add support for BPF_PROBE_MEM, by appending an exception table to the BPF program. If the load instruction causes a data abort, the fixup infrastructure finds the exception table and fixes up the fault, by clearing the destination register and jumping over the faulting instruction. A more generic solution would add a "handler" field to the table entry, like on x86 and s390. The same issue in ARM64 is fixed in 8008342853 ("bpf, arm64: Add BPF exception tables"). Signed-off-by: Tong Tiangen <tongtiangen@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: Pu Lehui <pulehui@huawei.com> Tested-by: Björn Töpel <bjorn@kernel.org> Acked-by: Björn Töpel <bjorn@kernel.org> Link: https://lore.kernel.org/bpf/20211027111822.3801679-1-tongtiangen@huawei.com		2021-10-28 01:02:44 +02:00
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cacheflush.c	mm: reorder includes after introduction of linux/pgtable.h	2020-06-09 09:39:13 -07:00
context.c	riscv: add ASID-based tlbflushing methods	2021-06-30 20:55:39 -07:00
extable.c	riscv, bpf: Add BPF exception tables	2021-10-28 01:02:44 +02:00
fault.c	riscv: Enable KFENCE for riscv64	2021-06-30 20:55:41 -07:00
hugetlbpage.c	hugetlbfs: remove hugetlb_add_hstate() warning for existing hstate	2020-06-03 20:09:46 -07:00
init.c	RISC-V Patches for the 5.15 Merge Window, Part 1	2021-09-05 11:31:23 -07:00
kasan_init.c	riscv: Ensure BPF_JIT_REGION_START aligned with PMD size	2021-06-18 21:10:05 -07:00
Makefile	riscv: Fixup patch_text panic in ftrace	2021-01-14 15:09:04 -08:00
pageattr.c	RISC-V Patches for the 5.11 Merge Window, Part 1	2020-12-18 10:43:07 -08:00
physaddr.c	riscv: Introduce structure that group all variables regarding kernel mapping	2021-07-05 18:04:00 -07:00
ptdump.c	riscv: Fix PTDUMP output now BPF region moved back to module region	2021-07-06 15:21:27 -07:00
tlbflush.c	riscv: add ASID-based tlbflushing methods	2021-06-30 20:55:39 -07:00