diff --git a/lib/std/crypto/ml_kem.zig b/lib/std/crypto/ml_kem.zig
index ea75d6ec8f..c04c5d1e83 100644
--- a/lib/std/crypto/ml_kem.zig
+++ b/lib/std/crypto/ml_kem.zig
@@ -1456,8 +1456,6 @@ fn randPolyNormalized(rnd: anytype) Poly {
 }
 
 test "MulHat" {
-    if (comptime builtin.cpu.has(.s390x, .vector)) return error.SkipZigTest;
-
     var rnd = RndGen.init(0);
 
     for (0..100) |_| {
@@ -1612,8 +1610,6 @@ test "Polynomial packing" {
 }
 
 test "Test inner PKE" {
-    if (comptime builtin.cpu.has(.s390x, .vector)) return error.SkipZigTest;
-
     var seed: [32]u8 = undefined;
     var pt: [32]u8 = undefined;
     for (&seed, &pt, 0..) |*s, *p, i| {
@@ -1635,8 +1631,6 @@ test "Test inner PKE" {
 }
 
 test "Test happy flow" {
-    if (comptime builtin.cpu.has(.s390x, .vector)) return error.SkipZigTest;
-
     var seed: [64]u8 = undefined;
     for (&seed, 0..) |*s, i| {
         s.* = @as(u8, @intCast(i));
@@ -1661,23 +1655,14 @@ test "Test happy flow" {
 // Code to test NIST Known Answer Tests (KAT), see PQCgenKAT.c.
 
 test "NIST KAT test d00.Kyber512" {
-    if (comptime builtin.cpu.has(.loongarch, .lsx)) return error.SkipZigTest;
-    if (comptime builtin.cpu.has(.s390x, .vector)) return error.SkipZigTest;
-
     try testNistKat(d00.Kyber512, "e9c2bd37133fcb40772f81559f14b1f58dccd1c816701be9ba6214d43baf4547");
 }
 
 test "NIST KAT test d00.Kyber1024" {
-    if (comptime builtin.cpu.has(.loongarch, .lsx)) return error.SkipZigTest;
-    if (comptime builtin.cpu.has(.s390x, .vector)) return error.SkipZigTest;
-
     try testNistKat(d00.Kyber1024, "89248f2f33f7f4f7051729111f3049c409a933ec904aedadf035f30fa5646cd5");
 }
 
 test "NIST KAT test d00.Kyber768" {
-    if (comptime builtin.cpu.has(.loongarch, .lsx)) return error.SkipZigTest;
-    if (comptime builtin.cpu.has(.s390x, .vector)) return error.SkipZigTest;
-
     try testNistKat(d00.Kyber768, "a1e122cad3c24bc51622e4c242d8b8acbcd3f618fee4220400605ca8f9ea02c2");
 }
 
diff --git a/lib/std/http/test.zig b/lib/std/http/test.zig
index e2add1d4db..4182a766c5 100644
--- a/lib/std/http/test.zig
+++ b/lib/std/http/test.zig
@@ -34,7 +34,7 @@ test "content length reader state update" {
 }
 
 test "trailers" {
-    if (builtin.cpu.arch.isPowerPC64() and builtin.mode != .Debug) return error.SkipZigTest; // https://github.com/llvm/llvm-project/issues/171879
+    if (builtin.cpu.arch.isPowerPC64() and builtin.mode != .Debug) return error.SkipZigTest; // https://github.com/llvm/llvm-project/issues/194257
     if (builtin.os.tag == .openbsd) return error.SkipZigTest; // https://codeberg.org/ziglang/zig/issues/30806
 
     const io = std.testing.io;
@@ -121,7 +121,7 @@ test "trailers" {
 }
 
 test "HTTP server handles a chunked transfer coding request" {
-    if (builtin.cpu.arch.isPowerPC64() and builtin.mode != .Debug) return error.SkipZigTest; // https://github.com/llvm/llvm-project/issues/171879
+    if (builtin.cpu.arch.isPowerPC64() and builtin.mode != .Debug) return error.SkipZigTest; // https://github.com/llvm/llvm-project/issues/194257
     if (builtin.os.tag == .openbsd) return error.SkipZigTest; // https://codeberg.org/ziglang/zig/issues/30806
 
     const io = std.testing.io;
@@ -190,7 +190,7 @@ test "HTTP server handles a chunked transfer coding request" {
 }
 
 test "echo content server" {
-    if (builtin.cpu.arch.isPowerPC64() and builtin.mode != .Debug) return error.SkipZigTest; // https://github.com/llvm/llvm-project/issues/171879
+    if (builtin.cpu.arch.isPowerPC64() and builtin.mode != .Debug) return error.SkipZigTest; // https://github.com/llvm/llvm-project/issues/194257
     if (builtin.os.tag == .openbsd) return error.SkipZigTest; // https://codeberg.org/ziglang/zig/issues/30806
 
     const io = std.testing.io;
@@ -281,7 +281,7 @@ test "echo content server" {
 }
 
 test "Server.Request.respondStreaming non-chunked, unknown content-length" {
-    if (builtin.cpu.arch.isPowerPC64() and builtin.mode != .Debug) return error.SkipZigTest; // https://github.com/llvm/llvm-project/issues/171879
+    if (builtin.cpu.arch.isPowerPC64() and builtin.mode != .Debug) return error.SkipZigTest; // https://github.com/llvm/llvm-project/issues/194257
     if (builtin.os.tag == .openbsd) return error.SkipZigTest; // https://codeberg.org/ziglang/zig/issues/30806
 
     const io = std.testing.io;
@@ -360,7 +360,7 @@ test "Server.Request.respondStreaming non-chunked, unknown content-length" {
 }
 
 test "receiving arbitrary http headers from the client" {
-    if (builtin.cpu.arch.isPowerPC64() and builtin.mode != .Debug) return error.SkipZigTest; // https://github.com/llvm/llvm-project/issues/171879
+    if (builtin.cpu.arch.isPowerPC64() and builtin.mode != .Debug) return error.SkipZigTest; // https://github.com/llvm/llvm-project/issues/194257
     if (builtin.os.tag == .openbsd) return error.SkipZigTest; // https://codeberg.org/ziglang/zig/issues/30806
 
     const io = std.testing.io;
@@ -426,7 +426,7 @@ test "receiving arbitrary http headers from the client" {
 }
 
 test "general client/server API coverage" {
-    if (builtin.cpu.arch.isPowerPC64() and builtin.mode != .Debug) return error.SkipZigTest; // https://github.com/llvm/llvm-project/issues/171879
+    if (builtin.cpu.arch.isPowerPC64() and builtin.mode != .Debug) return error.SkipZigTest; // https://github.com/llvm/llvm-project/issues/194257
     if (builtin.os.tag == .openbsd) return error.SkipZigTest; // https://codeberg.org/ziglang/zig/issues/30806
 
     const io = std.testing.io;
@@ -922,7 +922,7 @@ test "general client/server API coverage" {
 }
 
 test "Server streams both reading and writing" {
-    if (builtin.cpu.arch.isPowerPC64() and builtin.mode != .Debug) return error.SkipZigTest; // https://github.com/llvm/llvm-project/issues/171879
+    if (builtin.cpu.arch.isPowerPC64() and builtin.mode != .Debug) return error.SkipZigTest; // https://github.com/llvm/llvm-project/issues/194257
     if (builtin.os.tag == .openbsd) return error.SkipZigTest; // https://codeberg.org/ziglang/zig/issues/30806
 
     const io = std.testing.io;
@@ -1192,7 +1192,7 @@ fn createTestServer(io: Io, S: type) !*TestServer {
 }
 
 test "redirect to different connection" {
-    if (builtin.cpu.arch.isPowerPC64() and builtin.mode != .Debug) return error.SkipZigTest; // https://github.com/llvm/llvm-project/issues/171879
+    if (builtin.cpu.arch.isPowerPC64() and builtin.mode != .Debug) return error.SkipZigTest; // https://github.com/llvm/llvm-project/issues/194257
     if (builtin.os.tag == .openbsd) return error.SkipZigTest; // https://codeberg.org/ziglang/zig/issues/30806
 
     const io = std.testing.io;
@@ -1280,7 +1280,7 @@ test "redirect to different connection" {
 }
 
 test "boot failed connections from the pool" {
-    if (builtin.cpu.arch.isPowerPC64() and builtin.mode != .Debug) return error.SkipZigTest; // https://github.com/llvm/llvm-project/issues/171879
+    if (builtin.cpu.arch.isPowerPC64() and builtin.mode != .Debug) return error.SkipZigTest; // https://github.com/llvm/llvm-project/issues/194257
     if (builtin.os.tag == .openbsd) return error.SkipZigTest; // https://codeberg.org/ziglang/zig/issues/30806
 
     const io = std.testing.io;
diff --git a/lib/std/math/modf.zig b/lib/std/math/modf.zig
index 00ca26b01f..15515cde20 100644
--- a/lib/std/math/modf.zig
+++ b/lib/std/math/modf.zig
@@ -86,7 +86,7 @@ fn ModfTests(comptime T: type) type {
         }
         test "vector" {
             if (builtin.os.tag.isDarwin() and builtin.cpu.arch == .aarch64) return error.SkipZigTest;
-            if (builtin.cpu.arch == .s390x) return error.SkipZigTest;
+            if (builtin.cpu.arch == .s390x) return error.SkipZigTest; // https://github.com/llvm/llvm-project/issues/194256
 
             const widths = [_]comptime_int{ 1, 2, 3, 4, 8, 16 };
 
diff --git a/lib/std/zon/parse.zig b/lib/std/zon/parse.zig
index 9f492ddbea..4ae46ccb01 100644
--- a/lib/std/zon/parse.zig
+++ b/lib/std/zon/parse.zig
@@ -3129,7 +3129,7 @@ test "std.zon free on error" {
 
 test "std.zon vector" {
     if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // https://github.com/ziglang/zig/issues/15330
-    if (builtin.zig_backend == .stage2_llvm and builtin.cpu.arch == .s390x) return error.SkipZigTest; // github.com/ziglang/zig/issues/25957
+    if (builtin.zig_backend == .stage2_llvm and builtin.cpu.arch == .s390x) return error.SkipZigTest; // https://github.com/ziglang/zig/issues/25957
 
     const gpa = std.testing.allocator;