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authorLinus Torvalds <torvalds@linux-foundation.org>2026-10-02 12:17:24 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-10-02 12:17:24 -0700
commit3f1fe48a36b0b6722dc3fd421d93512bac138e9a (patch)
treeb767d7f6e26bc64334d3f14f8422d187239dc45d /lib/test_bitops.c
downloadlinux-stable-3f1fe48a36b0b6722dc3fd421d93512bac138e9a.tar.gz
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Merge tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linuxgrafted
Pull io_uring fixes from Jens Axboe: - Fix a task_work add use-after-free with SQPOLL. The sqpoll thread could pop and complete the last request while io_req_normal_work_add() was still looking at them after the mpscq push. Use the same approach as DEFER_TASKRUN to protect from that, holding an RCU read lock across the add, and have exit wait for an RCU grace period for SQPOLL rings as well. - CQE32 ring fixes: correct the free entry check for 32b CQEs, zero the big_cqe for aux CQEs, and only post the dummy skip CQE on CQE_MIXED rings - Mark the source filter table as COW when cloning bpf filters, so registering another filter on the source doesn't modify the shared table in place - Initialize the task context before running the BPF loop - Requeue zcrx multishot receives stopped by a local resource - End a TX_TIMESTAMP multishot cmd when the CQ is full (lollipopkit) * tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: io_uring: fix task_work add use-after-free with SQPOLL io_uring/cmd_net: end TX_TIMESTAMP multishot when the CQ is full io_uring/zcrx: requeue multishot receives stopped by a local resource io_uring: initialize task context before running the BPF loop io_uring: zero big_cqe for aux CQEs on CQE32 rings io_uring: fix free entry check for 32b CQEs on CQE32 rings io_uring: only post the dummy skip CQE on CQE_MIXED rings io_uring/bpf_filter: mark source as COW when cloning filters
Diffstat (limited to 'lib/test_bitops.c')
-rw-r--r--lib/test_bitops.c139
1 files changed, 139 insertions, 0 deletions
diff --git a/lib/test_bitops.c b/lib/test_bitops.c
new file mode 100644
index 000000000..55669624b
--- /dev/null
+++ b/lib/test_bitops.c
@@ -0,0 +1,139 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020 Intel Corporation
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/cleanup.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/printk.h>
+#include <linux/slab.h>
+
+/* a tiny module only meant to test
+ *
+ * set/clear_bit
+ * get_count_order/long
+ */
+
+/* use an enum because that's the most common BITMAP usage */
+enum bitops_fun {
+ BITOPS_4 = 4,
+ BITOPS_7 = 7,
+ BITOPS_11 = 11,
+ BITOPS_31 = 31,
+ BITOPS_88 = 88,
+ BITOPS_LAST = 255,
+ BITOPS_LENGTH = 256
+};
+
+static DECLARE_BITMAP(g_bitmap, BITOPS_LENGTH);
+
+static unsigned int order_comb[][2] = {
+ {0x00000003, 2},
+ {0x00000004, 2},
+ {0x00001fff, 13},
+ {0x00002000, 13},
+ {0x50000000, 31},
+ {0x80000000, 31},
+ {0x80003000, 32},
+};
+
+#ifdef CONFIG_64BIT
+static unsigned long order_comb_long[][2] = {
+ {0x0000000300000000, 34},
+ {0x0000000400000000, 34},
+ {0x00001fff00000000, 45},
+ {0x0000200000000000, 45},
+ {0x5000000000000000, 63},
+ {0x8000000000000000, 63},
+ {0x8000300000000000, 64},
+};
+#endif
+
+static int __init test_fns(void)
+{
+ static volatile __always_used unsigned long tmp __initdata;
+ unsigned long *buf __free(kfree) = NULL;
+ unsigned int i, n;
+ ktime_t time;
+
+ buf = kmalloc_array(10000, sizeof(unsigned long), GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ get_random_bytes(buf, 10000 * sizeof(unsigned long));
+ time = ktime_get();
+
+ for (n = 0; n < BITS_PER_LONG; n++)
+ for (i = 0; i < 10000; i++)
+ tmp = fns(buf[i], n);
+
+ time = ktime_get() - time;
+ pr_err("fns: %18llu ns\n", time);
+
+ return 0;
+}
+
+static int __init test_bitops_startup(void)
+{
+ int i, bit_set;
+
+ pr_info("Starting bitops test\n");
+ set_bit(BITOPS_4, g_bitmap);
+ set_bit(BITOPS_7, g_bitmap);
+ set_bit(BITOPS_11, g_bitmap);
+ set_bit(BITOPS_31, g_bitmap);
+ set_bit(BITOPS_88, g_bitmap);
+
+ for (i = 0; i < ARRAY_SIZE(order_comb); i++) {
+ if (order_comb[i][1] != get_count_order(order_comb[i][0]))
+ pr_warn("get_count_order wrong for %x\n",
+ order_comb[i][0]);
+ }
+
+ for (i = 0; i < ARRAY_SIZE(order_comb); i++) {
+ if (order_comb[i][1] != get_count_order_long(order_comb[i][0]))
+ pr_warn("get_count_order_long wrong for %x\n",
+ order_comb[i][0]);
+ }
+
+#ifdef CONFIG_64BIT
+ for (i = 0; i < ARRAY_SIZE(order_comb_long); i++) {
+ if (order_comb_long[i][1] !=
+ get_count_order_long(order_comb_long[i][0]))
+ pr_warn("get_count_order_long wrong for %lx\n",
+ order_comb_long[i][0]);
+ }
+#endif
+
+ barrier();
+
+ clear_bit(BITOPS_4, g_bitmap);
+ clear_bit(BITOPS_7, g_bitmap);
+ clear_bit(BITOPS_11, g_bitmap);
+ clear_bit(BITOPS_31, g_bitmap);
+ clear_bit(BITOPS_88, g_bitmap);
+
+ bit_set = find_first_bit(g_bitmap, BITOPS_LAST);
+ if (bit_set != BITOPS_LAST)
+ pr_err("ERROR: FOUND SET BIT %d\n", bit_set);
+
+ test_fns();
+
+ pr_info("Completed bitops test\n");
+
+ return 0;
+}
+
+static void __exit test_bitops_unstartup(void)
+{
+}
+
+module_init(test_bitops_startup);
+module_exit(test_bitops_unstartup);
+
+MODULE_AUTHOR("Jesse Brandeburg <jesse.brandeburg@intel.com>, Wei Yang <richard.weiyang@gmail.com>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Bit testing module");