diff mbox series

[bpf-next,04/10] s390/bpf: Land on the next JITed instruction after exception

Message ID 20240627090900.20017-5-iii@linux.ibm.com (mailing list archive)
State Superseded
Delegated to: BPF
Headers show
Series s390/bpf: Implement arena | expand

Checks

Context Check Description
bpf/vmtest-bpf-next-VM_Test-0 success Logs for Lint
bpf/vmtest-bpf-next-VM_Test-2 success Logs for Unittests
bpf/vmtest-bpf-next-VM_Test-1 success Logs for ShellCheck
bpf/vmtest-bpf-next-VM_Test-3 success Logs for Validate matrix.py
bpf/vmtest-bpf-next-VM_Test-5 success Logs for aarch64-gcc / build-release
bpf/vmtest-bpf-next-PR fail PR summary
bpf/vmtest-bpf-next-VM_Test-9 success Logs for s390x-gcc / build-release
bpf/vmtest-bpf-next-VM_Test-10 success Logs for s390x-gcc / test
bpf/vmtest-bpf-next-VM_Test-11 success Logs for s390x-gcc / veristat
bpf/vmtest-bpf-next-VM_Test-12 success Logs for set-matrix
bpf/vmtest-bpf-next-VM_Test-13 fail Logs for x86_64-gcc / build / build for x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-8 fail Logs for s390x-gcc / build / build for s390x with gcc
bpf/vmtest-bpf-next-VM_Test-7 success Logs for aarch64-gcc / veristat
bpf/vmtest-bpf-next-VM_Test-14 success Logs for x86_64-gcc / build-release
bpf/vmtest-bpf-next-VM_Test-15 success Logs for x86_64-gcc / test
bpf/vmtest-bpf-next-VM_Test-4 fail Logs for aarch64-gcc / build / build for aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-16 success Logs for x86_64-gcc / veristat
bpf/vmtest-bpf-next-VM_Test-6 success Logs for aarch64-gcc / test
bpf/vmtest-bpf-next-VM_Test-17 fail Logs for x86_64-llvm-17 / build / build for x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-18 fail Logs for x86_64-llvm-17 / build-release / build for x86_64 with llvm-17-O2
bpf/vmtest-bpf-next-VM_Test-19 success Logs for x86_64-llvm-17 / test
bpf/vmtest-bpf-next-VM_Test-20 success Logs for x86_64-llvm-17 / veristat
bpf/vmtest-bpf-next-VM_Test-21 fail Logs for x86_64-llvm-18 / build / build for x86_64 with llvm-18
bpf/vmtest-bpf-next-VM_Test-22 fail Logs for x86_64-llvm-18 / build-release / build for x86_64 with llvm-18-O2
bpf/vmtest-bpf-next-VM_Test-23 success Logs for x86_64-llvm-18 / test
bpf/vmtest-bpf-next-VM_Test-24 success Logs for x86_64-llvm-18 / veristat
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for bpf-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 8 this patch: 8
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 12 maintainers not CCed: yonghong.song@linux.dev svens@linux.ibm.com haoluo@google.com linux-s390@vger.kernel.org jolsa@kernel.org song@kernel.org john.fastabend@gmail.com eddyz87@gmail.com kpsingh@kernel.org martin.lau@linux.dev sdf@google.com borntraeger@linux.ibm.com
netdev/build_clang success Errors and warnings before: 8 this patch: 8
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 8 this patch: 8
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 14 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Ilya Leoshkevich June 27, 2024, 9:07 a.m. UTC 
Currently we land on the nop, which is unnecessary: we can just as well
begin executing the next instruction. Furthermore, the upcoming arena
support for the loop-based BPF_XCHG implementation will require landing
on an instruction that comes after the loop.

So land on the next JITed instruction, which covers both cases.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
---
 arch/s390/net/bpf_jit_comp.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c
index 582fa3830772..ecd53f8f0602 100644
--- a/arch/s390/net/bpf_jit_comp.c
+++ b/arch/s390/net/bpf_jit_comp.c
@@ -747,10 +747,11 @@  static int bpf_jit_probe_post(struct bpf_jit *jit, struct bpf_prog *fp,
 			return -1;
 		ex->insn = delta;
 		/*
-		 * Always land on the nop. Note that extable infrastructure
-		 * ignores fixup field, it is handled by ex_handler_bpf().
+		 * Land on the current instruction. Note that the extable
+		 * infrastructure ignores the fixup field; it is handled by
+		 * ex_handler_bpf().
 		 */
-		delta = jit->prg_buf + probe->nop_prg - (u8 *)&ex->fixup;
+		delta = jit->prg_buf + jit->prg - (u8 *)&ex->fixup;
 		if (WARN_ON_ONCE(delta < INT_MIN || delta > INT_MAX))
 			/* JIT bug - landing pad and extable must be close. */
 			return -1;