From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops There's some internal state that ftrace_ops needs to have set, but since it can be declared outside of the ftrace.c code, it calls ftrace_ops_init() on the ops in every global function. The issue is that if two tasks call it on the same ops at the same time it is possible to have the initialization of one corrupt the initialization of the other call. Create a ops_mutex to use to synchronize every initialization of the ftrace_ops. The mutex is taken within checking the ftrace_ops flag that states it was initializied but the flag is checked again after the mutex has been taken. Checking first outside the mutex allows it to shortcut having to take the mutex. But then the check needs to be done again after the mute is taken in case of races. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock") Reported-by: sashiko-bot@kernel.org Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt --- crypto/async_tx/raid6test.c | 250 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 250 insertions(+) create mode 100644 crypto/async_tx/raid6test.c (limited to 'crypto/async_tx/raid6test.c') diff --git a/crypto/async_tx/raid6test.c b/crypto/async_tx/raid6test.c new file mode 100644 index 000000000..d3fbee1e0 --- /dev/null +++ b/crypto/async_tx/raid6test.c @@ -0,0 +1,250 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * asynchronous raid6 recovery self test + * Copyright (c) 2009, Intel Corporation. + * + * based on drivers/md/raid6test/test.c: + * Copyright 2002-2007 H. Peter Anvin + */ +#include +#include +#include +#include +#include + +#undef pr +#define pr(fmt, args...) pr_info("raid6test: " fmt, ##args) + +#define NDISKS 64 /* Including P and Q */ + +static struct page *dataptrs[NDISKS]; +unsigned int dataoffs[NDISKS]; +static addr_conv_t addr_conv[NDISKS]; +static struct page *data[NDISKS+3]; +static struct page *spare; +static struct page *recovi; +static struct page *recovj; + +static void callback(void *param) +{ + struct completion *cmp = param; + + complete(cmp); +} + +static void makedata(int disks) +{ + int i; + + for (i = 0; i < disks; i++) { + get_random_bytes(page_address(data[i]), PAGE_SIZE); + dataptrs[i] = data[i]; + dataoffs[i] = 0; + } +} + +static char disk_type(int d, int disks) +{ + if (d == disks - 2) + return 'P'; + else if (d == disks - 1) + return 'Q'; + else + return 'D'; +} + +/* Recover two failed blocks. */ +static void raid6_dual_recov(int disks, size_t bytes, int faila, int failb, + struct page **ptrs, unsigned int *offs) +{ + struct async_submit_ctl submit; + struct completion cmp; + struct dma_async_tx_descriptor *tx = NULL; + enum sum_check_flags result = ~0; + + if (faila > failb) + swap(faila, failb); + + if (failb == disks-1) { + if (faila == disks-2) { + /* P+Q failure. Just rebuild the syndrome. */ + init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv); + tx = async_gen_syndrome(ptrs, offs, + disks, bytes, &submit); + } else { + struct page *blocks[NDISKS]; + struct page *dest; + int count = 0; + int i; + + BUG_ON(disks > NDISKS); + + /* data+Q failure. Reconstruct data from P, + * then rebuild syndrome + */ + for (i = disks; i-- ; ) { + if (i == faila || i == failb) + continue; + blocks[count++] = ptrs[i]; + } + dest = ptrs[faila]; + init_async_submit(&submit, ASYNC_TX_XOR_ZERO_DST, NULL, + NULL, NULL, addr_conv); + tx = async_xor(dest, blocks, 0, count, bytes, &submit); + + init_async_submit(&submit, 0, tx, NULL, NULL, addr_conv); + tx = async_gen_syndrome(ptrs, offs, + disks, bytes, &submit); + } + } else { + if (failb == disks-2) { + /* data+P failure. */ + init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv); + tx = async_raid6_datap_recov(disks, bytes, + faila, ptrs, offs, &submit); + } else { + /* data+data failure. */ + init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv); + tx = async_raid6_2data_recov(disks, bytes, + faila, failb, ptrs, offs, &submit); + } + } + init_completion(&cmp); + init_async_submit(&submit, ASYNC_TX_ACK, tx, callback, &cmp, addr_conv); + tx = async_syndrome_val(ptrs, offs, + disks, bytes, &result, spare, 0, &submit); + async_tx_issue_pending(tx); + + if (wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)) == 0) + pr("%s: timeout! (faila: %d failb: %d disks: %d)\n", + __func__, faila, failb, disks); + + if (result != 0) + pr("%s: validation failure! faila: %d failb: %d sum_check_flags: %x\n", + __func__, faila, failb, result); +} + +static int test_disks(int i, int j, int disks) +{ + int erra, errb; + + memset(page_address(recovi), 0xf0, PAGE_SIZE); + memset(page_address(recovj), 0xba, PAGE_SIZE); + + dataptrs[i] = recovi; + dataptrs[j] = recovj; + + raid6_dual_recov(disks, PAGE_SIZE, i, j, dataptrs, dataoffs); + + erra = memcmp(page_address(data[i]), page_address(recovi), PAGE_SIZE); + errb = memcmp(page_address(data[j]), page_address(recovj), PAGE_SIZE); + + pr("%s(%d, %d): faila=%3d(%c) failb=%3d(%c) %s\n", + __func__, i, j, i, disk_type(i, disks), j, disk_type(j, disks), + (!erra && !errb) ? "OK" : !erra ? "ERRB" : !errb ? "ERRA" : "ERRAB"); + + dataptrs[i] = data[i]; + dataptrs[j] = data[j]; + + return erra || errb; +} + +static int test(int disks, int *tests) +{ + struct dma_async_tx_descriptor *tx; + struct async_submit_ctl submit; + struct completion cmp; + int err = 0; + int i, j; + + recovi = data[disks]; + recovj = data[disks+1]; + spare = data[disks+2]; + + makedata(disks); + + /* Nuke syndromes */ + memset(page_address(data[disks-2]), 0xee, PAGE_SIZE); + memset(page_address(data[disks-1]), 0xee, PAGE_SIZE); + + /* Generate assumed good syndrome */ + init_completion(&cmp); + init_async_submit(&submit, ASYNC_TX_ACK, NULL, callback, &cmp, addr_conv); + tx = async_gen_syndrome(dataptrs, dataoffs, disks, PAGE_SIZE, &submit); + async_tx_issue_pending(tx); + + if (wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)) == 0) { + pr("error: initial gen_syndrome(%d) timed out\n", disks); + return 1; + } + + pr("testing the %d-disk case...\n", disks); + for (i = 0; i < disks-1; i++) + for (j = i+1; j < disks; j++) { + (*tests)++; + err += test_disks(i, j, disks); + } + + return err; +} + + +static int __init raid6_test(void) +{ + int err = 0; + int tests = 0; + int i; + + for (i = 0; i < NDISKS+3; i++) { + data[i] = alloc_page(GFP_KERNEL); + if (!data[i]) { + while (i--) + put_page(data[i]); + return -ENOMEM; + } + } + + /* the 4-disk and 5-disk cases are special for the recovery code */ + if (NDISKS > 4) + err += test(4, &tests); + if (NDISKS > 5) + err += test(5, &tests); + /* the 11 and 12 disk cases are special for ioatdma (p-disabled + * q-continuation without extended descriptor) + */ + if (NDISKS > 12) { + err += test(11, &tests); + err += test(12, &tests); + } + + /* the 24 disk case is special for ioatdma as it is the boundary point + * at which it needs to switch from 8-source ops to 16-source + * ops for continuation (assumes DMA_HAS_PQ_CONTINUE is not set) + */ + if (NDISKS > 24) + err += test(24, &tests); + + err += test(NDISKS, &tests); + + pr("\n"); + pr("complete (%d tests, %d failure%s)\n", + tests, err, err == 1 ? "" : "s"); + + for (i = 0; i < NDISKS+3; i++) + put_page(data[i]); + + return 0; +} + +static void __exit raid6_test_exit(void) +{ +} + +/* when compiled-in wait for drivers to load first (assumes dma drivers + * are also compiled-in) + */ +late_initcall(raid6_test); +module_exit(raid6_test_exit); +MODULE_AUTHOR("Dan Williams "); +MODULE_DESCRIPTION("asynchronous RAID-6 recovery self tests"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1