[PATCH bpf-next v2] selftests/bpf: Enable signed overflow and small value tests for LoongArch

[PATCH bpf-next v2] selftests/bpf: Enable signed overflow and small value tests for LoongArch

[Tiezhu Yang]

The LoongArch hardware divider handles signed overflow boundaries (such
as INT_MIN/-1 or LLONG_MIN/-1) natively and perfectly well on physical
silicon: (1) for division operations, it naturally returns the dividend
itself; (2) for modulo operations, it returns 0.

Furthermore, small value signed calculations with negative divisors work
correctly as expected.

Thus add the __arch_loongarch macro tag to these 16 test cases to enable
them for LoongArch in verifier_sdiv.c.

Before:
  $ sudo ./test_progs -t verifier_sdiv | tail -1
  Summary: 1/128 PASSED, 16 SKIPPED, 0/0 FAILED

After:
  $ sudo ./test_progs -t verifier_sdiv | tail -1
  Summary: 1/144 PASSED, 0 SKIPPED, 0/0 FAILED

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
---
 .../testing/selftests/bpf/progs/verifier_sdiv.c  | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/tools/testing/selftests/bpf/progs/verifier_sdiv.c b/tools/testing/selftests/bpf/progs/verifier_sdiv.c
index d6cbe1e27fd6..4ac92335da91 100644
--- a/tools/testing/selftests/bpf/progs/verifier_sdiv.c
+++ b/tools/testing/selftests/bpf/progs/verifier_sdiv.c
@@ -775,6 +775,7 @@ SEC("socket")
 __description("SDIV64, overflow r/r, LLONG_MIN/-1")
 __success __retval(1)
 __arch_x86_64
+__arch_loongarch
 __xlated("0: r2 = 0x8000000000000000")
 __xlated("2: r3 = -1")
 __xlated("3: r4 = r2")
@@ -810,6 +811,7 @@ SEC("socket")
 __description("SDIV64, r/r, small_val/-1")
 __success __retval(-5)
 __arch_x86_64
+__arch_loongarch
 __xlated("0: r2 = 5")
 __xlated("1: r3 = -1")
 __xlated("2: r12 = r3")
@@ -839,6 +841,7 @@ SEC("socket")
 __description("SDIV64, overflow r/i, LLONG_MIN/-1")
 __success __retval(1)
 __arch_x86_64
+__arch_loongarch
 __xlated("0: r2 = 0x8000000000000000")
 __xlated("2: r4 = r2")
 __xlated("3: r2 = -r2")
@@ -865,6 +868,7 @@ SEC("socket")
 __description("SDIV64, r/i, small_val/-1")
 __success __retval(-5)
 __arch_x86_64
+__arch_loongarch
 __xlated("0: r2 = 5")
 __xlated("1: r4 = r2")
 __xlated("2: r2 = -r2")
@@ -887,6 +891,7 @@ SEC("socket")
 __description("SDIV32, overflow r/r, INT_MIN/-1")
 __success __retval(1)
 __arch_x86_64
+__arch_loongarch
 __xlated("0: w2 = -2147483648")
 __xlated("1: w3 = -1")
 __xlated("2: w4 = w2")
@@ -922,6 +927,7 @@ SEC("socket")
 __description("SDIV32, r/r, small_val/-1")
 __success __retval(5)
 __arch_x86_64
+__arch_loongarch
 __xlated("0: w2 = -5")
 __xlated("1: w3 = -1")
 __xlated("2: w4 = w2")
@@ -953,6 +959,7 @@ SEC("socket")
 __description("SDIV32, overflow r/i, INT_MIN/-1")
 __success __retval(1)
 __arch_x86_64
+__arch_loongarch
 __xlated("0: w2 = -2147483648")
 __xlated("1: w4 = w2")
 __xlated("2: w2 = -w2")
@@ -979,6 +986,7 @@ SEC("socket")
 __description("SDIV32, r/i, small_val/-1")
 __success __retval(-5)
 __arch_x86_64
+__arch_loongarch
 __xlated("0: w2 = 5")
 __xlated("1: w4 = w2")
 __xlated("2: w2 = -w2")
@@ -1001,6 +1009,7 @@ SEC("socket")
 __description("SMOD64, overflow r/r, LLONG_MIN/-1")
 __success __retval(0)
 __arch_x86_64
+__arch_loongarch
 __xlated("0: r2 = 0x8000000000000000")
 __xlated("2: r3 = -1")
 __xlated("3: r4 = r2")
@@ -1031,6 +1040,7 @@ SEC("socket")
 __description("SMOD64, r/r, small_val/-1")
 __success __retval(0)
 __arch_x86_64
+__arch_loongarch
 __xlated("0: r2 = 5")
 __xlated("1: r3 = -1")
 __xlated("2: r4 = r2")
@@ -1061,6 +1071,7 @@ SEC("socket")
 __description("SMOD64, overflow r/i, LLONG_MIN/-1")
 __success __retval(0)
 __arch_x86_64
+__arch_loongarch
 __xlated("0: r2 = 0x8000000000000000")
 __xlated("2: r4 = r2")
 __xlated("3: w2 = 0")
@@ -1083,6 +1094,7 @@ SEC("socket")
 __description("SMOD64, r/i, small_val/-1")
 __success __retval(0)
 __arch_x86_64
+__arch_loongarch
 __xlated("0: r2 = 5")
 __xlated("1: r4 = r2")
 __xlated("2: w2 = 0")
@@ -1105,6 +1117,7 @@ SEC("socket")
 __description("SMOD32, overflow r/r, INT_MIN/-1")
 __success __retval(0)
 __arch_x86_64
+__arch_loongarch
 __xlated("0: w2 = -2147483648")
 __xlated("1: w3 = -1")
 __xlated("2: w4 = w2")
@@ -1137,6 +1150,7 @@ SEC("socket")
 __description("SMOD32, r/r, small_val/-1")
 __success __retval(0)
 __arch_x86_64
+__arch_loongarch
 __xlated("0: w2 = -5")
 __xlated("1: w3 = -1")
 __xlated("2: w4 = w2")
@@ -1169,6 +1183,7 @@ SEC("socket")
 __description("SMOD32, overflow r/i, INT_MIN/-1")
 __success __retval(0)
 __arch_x86_64
+__arch_loongarch
 __xlated("0: w2 = -2147483648")
 __xlated("1: w4 = w2")
 __xlated("2: w2 = 0")
@@ -1191,6 +1206,7 @@ SEC("socket")
 __description("SMOD32, r/i, small_val/-1")
 __success __retval(0)
 __arch_x86_64
+__arch_loongarch
 __xlated("0: w2 = 5")
 __xlated("1: w4 = w2")
 __xlated("2: w2 = 0")
-- 
2.42.0

Re: [PATCH bpf-next v2] selftests/bpf: Enable signed overflow and small value tests for LoongArch

[patchwork-bot+netdevbpf]

Hello:

This patch was applied to bpf/bpf-next.git (master)
by Andrii Nakryiko <andrii@kernel.org>:

On Fri, 30 Oct 2026 17:13:05 +0800 you wrote:
> The LoongArch hardware divider handles signed overflow boundaries (such
> as INT_MIN/-1 or LLONG_MIN/-1) natively and perfectly well on physical
> silicon: (1) for division operations, it naturally returns the dividend
> itself; (2) for modulo operations, it returns 0.
> 
> Furthermore, small value signed calculations with negative divisors work
> correctly as expected.
> 
> [...]

Here is the summary with links:
  - [bpf-next,v2] selftests/bpf: Enable signed overflow and small value tests for LoongArch
    https://git.kernel.org/bpf/bpf-next/c/aef18c73c961

You are awesome, thank you!
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