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 --- block/partitions/mac.c | 157 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 157 insertions(+) create mode 100644 block/partitions/mac.c (limited to 'block/partitions/mac.c') diff --git a/block/partitions/mac.c b/block/partitions/mac.c new file mode 100644 index 000000000..df03ca428 --- /dev/null +++ b/block/partitions/mac.c @@ -0,0 +1,157 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * fs/partitions/mac.c + * + * Code extracted from drivers/block/genhd.c + * Copyright (C) 1991-1998 Linus Torvalds + * Re-organised Feb 1998 Russell King + */ + +#include +#include "check.h" +#include "mac.h" + +#ifdef CONFIG_PPC_PMAC +#include +extern void note_bootable_part(dev_t dev, int part, int goodness); +#endif + +/* + * Code to understand MacOS partition tables. + */ + +#ifdef CONFIG_PPC_PMAC +static inline void mac_fix_string(char *stg, int len) +{ + int i; + + for (i = len - 1; i >= 0 && stg[i] == ' '; i--) + stg[i] = 0; +} +#endif + +int mac_partition(struct parsed_partitions *state) +{ + Sector sect; + unsigned char *data; + int slot, blocks_in_map; + unsigned secsize, datasize, partoffset; +#ifdef CONFIG_PPC_PMAC + int found_root = 0; + int found_root_goodness = 0; +#endif + struct mac_partition *part; + struct mac_driver_desc *md; + + /* Get 0th block and look at the first partition map entry. */ + md = read_part_sector(state, 0, §); + if (!md) + return -1; + if (be16_to_cpu(md->signature) != MAC_DRIVER_MAGIC) { + put_dev_sector(sect); + return 0; + } + secsize = be16_to_cpu(md->block_size); + put_dev_sector(sect); + + /* + * If the "block size" is not a power of 2, things get weird - we might + * end up with a partition straddling a sector boundary, so we wouldn't + * be able to read a partition entry with read_part_sector(). + * Real block sizes are probably (?) powers of two, so just require + * that. + */ + if (!is_power_of_2(secsize)) + return -1; + datasize = round_down(secsize, 512); + data = read_part_sector(state, datasize / 512, §); + if (!data) + return -1; + partoffset = secsize % 512; + if (partoffset + sizeof(*part) > datasize) { + put_dev_sector(sect); + return -1; + } + part = (struct mac_partition *) (data + partoffset); + if (be16_to_cpu(part->signature) != MAC_PARTITION_MAGIC) { + put_dev_sector(sect); + return 0; /* not a MacOS disk */ + } + blocks_in_map = be32_to_cpu(part->map_count); + if (blocks_in_map < 0 || blocks_in_map >= DISK_MAX_PARTS) { + put_dev_sector(sect); + return 0; + } + + if (blocks_in_map >= state->limit) + blocks_in_map = state->limit - 1; + + seq_buf_puts(&state->pp_buf, " [mac]"); + for (slot = 1; slot <= blocks_in_map; ++slot) { + int pos = slot * secsize; + put_dev_sector(sect); + data = read_part_sector(state, pos/512, §); + if (!data) + return -1; + part = (struct mac_partition *) (data + pos%512); + if (be16_to_cpu(part->signature) != MAC_PARTITION_MAGIC) + break; + put_partition(state, slot, + be32_to_cpu(part->start_block) * (secsize/512), + be32_to_cpu(part->block_count) * (secsize/512)); + + if (!strncasecmp(part->type, "Linux_RAID", 10)) + state->parts[slot].flags = ADDPART_FLAG_RAID; +#ifdef CONFIG_PPC_PMAC + /* + * If this is the first bootable partition, tell the + * setup code, in case it wants to make this the root. + */ + if (machine_is(powermac)) { + int goodness = 0; + + mac_fix_string(part->processor, 16); + mac_fix_string(part->name, 32); + mac_fix_string(part->type, 32); + + if ((be32_to_cpu(part->status) & MAC_STATUS_BOOTABLE) + && strcasecmp(part->processor, "powerpc") == 0) + goodness++; + + if (strcasecmp(part->type, "Apple_UNIX_SVR2") == 0 + || (strncasecmp(part->type, "Linux", 5) == 0 + && strcasecmp(part->type, "Linux_swap") != 0)) { + int i, l; + + goodness++; + l = strnlen(part->name, sizeof(part->name)); + if (strncmp(part->name, "/", sizeof(part->name)) == 0) + goodness++; + for (i = 0; i <= l - 4; ++i) { + if (strncasecmp(part->name + i, "root", + 4) == 0) { + goodness += 2; + break; + } + } + if (strncasecmp(part->name, "swap", 4) == 0) + goodness--; + } + + if (goodness > found_root_goodness) { + found_root = slot; + found_root_goodness = goodness; + } + } +#endif /* CONFIG_PPC_PMAC */ + } +#ifdef CONFIG_PPC_PMAC + if (found_root_goodness) + note_bootable_part(state->disk->part0->bd_dev, found_root, + found_root_goodness); +#endif + + put_dev_sector(sect); + seq_buf_puts(&state->pp_buf, "\n"); + return 1; +} -- cgit v1.3.1