mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 09:19:51 +00:00
![Linus Torvalds](/assets/img/avatar_default.png)
Fixes: - Fix early access to cpu_spec relocation from Benjamin Herrenschmidt - Fix incorrect event codes in power9-event-list from Madhavan Srinivasan - Move register_process_table() out of ppc_md from Michael Ellerman Use jump_label for [cpu|mmu]_has_feature() from Aneesh Kumar K.V, Kevin Hao and Michael Ellerman: - Add mmu_early_init_devtree() from Michael Ellerman - Move disable_radix handling into mmu_early_init_devtree() from Michael Ellerman - Do hash device tree scanning earlier from Michael Ellerman - Do radix device tree scanning earlier from Michael Ellerman - Do feature patching before MMU init from Michael Ellerman - Check features don't change after patching from Michael Ellerman - Make MMU_FTR_RADIX a MMU family feature from Aneesh Kumar K.V - Convert mmu_has_feature() to returning bool from Michael Ellerman - Convert cpu_has_feature() to returning bool from Michael Ellerman - Define radix_enabled() in one place & use static inline from Michael Ellerman - Add early_[cpu|mmu]_has_feature() from Michael Ellerman - Convert early cpu/mmu feature check to use the new helpers from Aneesh Kumar K.V - jump_label: Make it possible for arches to invoke jump_label_init() earlier from Kevin Hao - Call jump_label_init() in apply_feature_fixups() from Aneesh Kumar K.V - Remove mfvtb() from Kevin Hao - Move cpu_has_feature() to a separate file from Kevin Hao - Add kconfig option to use jump labels for cpu/mmu_has_feature() from Michael Ellerman - Add option to use jump label for cpu_has_feature() from Kevin Hao - Add option to use jump label for mmu_has_feature() from Kevin Hao - Catch usage of cpu/mmu_has_feature() before jump label init from Aneesh Kumar K.V - Annotate jump label assembly from Michael Ellerman TLB flush enhancements from Aneesh Kumar K.V: - radix: Implement tlb mmu gather flush efficiently - Add helper for finding SLBE LLP encoding - Use hugetlb flush functions - Drop multiple definition of mm_is_core_local - radix: Add tlb flush of THP ptes - radix: Rename function and drop unused arg - radix/hugetlb: Add helper for finding page size - hugetlb: Add flush_hugetlb_tlb_range - remove flush_tlb_page_nohash Add new ptrace regsets from Anshuman Khandual and Simon Guo: - elf: Add powerpc specific core note sections - Add the function flush_tmregs_to_thread - Enable in transaction NT_PRFPREG ptrace requests - Enable in transaction NT_PPC_VMX ptrace requests - Enable in transaction NT_PPC_VSX ptrace requests - Adapt gpr32_get, gpr32_set functions for transaction - Enable support for NT_PPC_CGPR - Enable support for NT_PPC_CFPR - Enable support for NT_PPC_CVMX - Enable support for NT_PPC_CVSX - Enable support for TM SPR state - Enable NT_PPC_TM_CTAR, NT_PPC_TM_CPPR, NT_PPC_TM_CDSCR - Enable support for NT_PPPC_TAR, NT_PPC_PPR, NT_PPC_DSCR - Enable support for EBB registers - Enable support for Performance Monitor registers -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJXpGaLAAoJEFHr6jzI4aWA9aYP/1AqmRPJ9D0XVUJWT+FVABUK LESESoVFF4Hug1j1F8Synhg5o4SzD2t45iGKbclYaFthOIyovMg7Wr1KSu4hQ0go rPuQfpXDNQ8jKdDX8hbPXKUxrNRBNfqJGFo5E7mO6wN9AJ9d1LVwQ+jKAva29Tqs LaAlMbQNbeObPNzOl73B73iew3aozr+mXjBqv82lqvgYknBD2CLf24xGG3eNIbq5 ZZk4LPC8pdkaxnajnzRFzqwiyPWzao0yfpVRKh52TKHBQF/prR/KACb6zUuja/61 krOfegUKob14OYrehjs6X8XNRLnILRI0u1H5bmj7eVEiY/usyNzE93SMHZM3Wdau sQF/Au4OLNXj0ZQdNBtzRsZRyp1d560Gsj+lQGBoPd4hfIWkFYHvxzxsUSdqv4uA MWDMwN0Vvfk0cpprsabsWNevkaotYYBU00px5hF/e5ZUc9/x/xYUVMgPEDr0QZLr cHJo9/Pjk4u/0g4lj+2y1LLl/0tNEZZg69O6bvffPAPVSS4/P4y/bKKYd4I0zL99 Ykp91mSmkl70F3edgOSFqyda2gN2l2Ekb/i081YGXheFy1rbD29Vxv82BOVog4KY ibvOqp38WDzCVk5OXuCRvBl0VudLKGJYdppU1nXg4KgrTZXHeCAC0E+NzUsgOF4k OMvQ+5drVxrno+Hw8FVJ =0Q8E -----END PGP SIGNATURE----- Merge tag 'powerpc-4.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull more powerpc updates from Michael Ellerman: "These were delayed for various reasons, so I let them sit in next a bit longer, rather than including them in my first pull request. Fixes: - Fix early access to cpu_spec relocation from Benjamin Herrenschmidt - Fix incorrect event codes in power9-event-list from Madhavan Srinivasan - Move register_process_table() out of ppc_md from Michael Ellerman Use jump_label use for [cpu|mmu]_has_feature(): - Add mmu_early_init_devtree() from Michael Ellerman - Move disable_radix handling into mmu_early_init_devtree() from Michael Ellerman - Do hash device tree scanning earlier from Michael Ellerman - Do radix device tree scanning earlier from Michael Ellerman - Do feature patching before MMU init from Michael Ellerman - Check features don't change after patching from Michael Ellerman - Make MMU_FTR_RADIX a MMU family feature from Aneesh Kumar K.V - Convert mmu_has_feature() to returning bool from Michael Ellerman - Convert cpu_has_feature() to returning bool from Michael Ellerman - Define radix_enabled() in one place & use static inline from Michael Ellerman - Add early_[cpu|mmu]_has_feature() from Michael Ellerman - Convert early cpu/mmu feature check to use the new helpers from Aneesh Kumar K.V - jump_label: Make it possible for arches to invoke jump_label_init() earlier from Kevin Hao - Call jump_label_init() in apply_feature_fixups() from Aneesh Kumar K.V - Remove mfvtb() from Kevin Hao - Move cpu_has_feature() to a separate file from Kevin Hao - Add kconfig option to use jump labels for cpu/mmu_has_feature() from Michael Ellerman - Add option to use jump label for cpu_has_feature() from Kevin Hao - Add option to use jump label for mmu_has_feature() from Kevin Hao - Catch usage of cpu/mmu_has_feature() before jump label init from Aneesh Kumar K.V - Annotate jump label assembly from Michael Ellerman TLB flush enhancements from Aneesh Kumar K.V: - radix: Implement tlb mmu gather flush efficiently - Add helper for finding SLBE LLP encoding - Use hugetlb flush functions - Drop multiple definition of mm_is_core_local - radix: Add tlb flush of THP ptes - radix: Rename function and drop unused arg - radix/hugetlb: Add helper for finding page size - hugetlb: Add flush_hugetlb_tlb_range - remove flush_tlb_page_nohash Add new ptrace regsets from Anshuman Khandual and Simon Guo: - elf: Add powerpc specific core note sections - Add the function flush_tmregs_to_thread - Enable in transaction NT_PRFPREG ptrace requests - Enable in transaction NT_PPC_VMX ptrace requests - Enable in transaction NT_PPC_VSX ptrace requests - Adapt gpr32_get, gpr32_set functions for transaction - Enable support for NT_PPC_CGPR - Enable support for NT_PPC_CFPR - Enable support for NT_PPC_CVMX - Enable support for NT_PPC_CVSX - Enable support for TM SPR state - Enable NT_PPC_TM_CTAR, NT_PPC_TM_CPPR, NT_PPC_TM_CDSCR - Enable support for NT_PPPC_TAR, NT_PPC_PPR, NT_PPC_DSCR - Enable support for EBB registers - Enable support for Performance Monitor registers" * tag 'powerpc-4.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (48 commits) powerpc/mm: Move register_process_table() out of ppc_md powerpc/perf: Fix incorrect event codes in power9-event-list powerpc/32: Fix early access to cpu_spec relocation powerpc/ptrace: Enable support for Performance Monitor registers powerpc/ptrace: Enable support for EBB registers powerpc/ptrace: Enable support for NT_PPPC_TAR, NT_PPC_PPR, NT_PPC_DSCR powerpc/ptrace: Enable NT_PPC_TM_CTAR, NT_PPC_TM_CPPR, NT_PPC_TM_CDSCR powerpc/ptrace: Enable support for TM SPR state powerpc/ptrace: Enable support for NT_PPC_CVSX powerpc/ptrace: Enable support for NT_PPC_CVMX powerpc/ptrace: Enable support for NT_PPC_CFPR powerpc/ptrace: Enable support for NT_PPC_CGPR powerpc/ptrace: Adapt gpr32_get, gpr32_set functions for transaction powerpc/ptrace: Enable in transaction NT_PPC_VSX ptrace requests powerpc/ptrace: Enable in transaction NT_PPC_VMX ptrace requests powerpc/ptrace: Enable in transaction NT_PRFPREG ptrace requests powerpc/process: Add the function flush_tmregs_to_thread elf: Add powerpc specific core note sections powerpc/mm: remove flush_tlb_page_nohash powerpc/mm/hugetlb: Add flush_hugetlb_tlb_range ...
611 lines
15 KiB
C
611 lines
15 KiB
C
/*
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* jump label support
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*
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* Copyright (C) 2009 Jason Baron <jbaron@redhat.com>
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* Copyright (C) 2011 Peter Zijlstra
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*
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*/
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#include <linux/memory.h>
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#include <linux/uaccess.h>
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#include <linux/module.h>
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#include <linux/list.h>
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#include <linux/slab.h>
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#include <linux/sort.h>
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#include <linux/err.h>
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#include <linux/static_key.h>
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#include <linux/jump_label_ratelimit.h>
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#include <linux/bug.h>
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#ifdef HAVE_JUMP_LABEL
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/* mutex to protect coming/going of the the jump_label table */
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static DEFINE_MUTEX(jump_label_mutex);
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void jump_label_lock(void)
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{
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mutex_lock(&jump_label_mutex);
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}
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void jump_label_unlock(void)
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{
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mutex_unlock(&jump_label_mutex);
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}
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static int jump_label_cmp(const void *a, const void *b)
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{
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const struct jump_entry *jea = a;
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const struct jump_entry *jeb = b;
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if (jea->key < jeb->key)
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return -1;
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if (jea->key > jeb->key)
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return 1;
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return 0;
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}
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static void
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jump_label_sort_entries(struct jump_entry *start, struct jump_entry *stop)
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{
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unsigned long size;
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size = (((unsigned long)stop - (unsigned long)start)
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/ sizeof(struct jump_entry));
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sort(start, size, sizeof(struct jump_entry), jump_label_cmp, NULL);
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}
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static void jump_label_update(struct static_key *key);
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/*
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* There are similar definitions for the !HAVE_JUMP_LABEL case in jump_label.h.
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* The use of 'atomic_read()' requires atomic.h and its problematic for some
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* kernel headers such as kernel.h and others. Since static_key_count() is not
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* used in the branch statements as it is for the !HAVE_JUMP_LABEL case its ok
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* to have it be a function here. Similarly, for 'static_key_enable()' and
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* 'static_key_disable()', which require bug.h. This should allow jump_label.h
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* to be included from most/all places for HAVE_JUMP_LABEL.
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*/
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int static_key_count(struct static_key *key)
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{
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/*
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* -1 means the first static_key_slow_inc() is in progress.
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* static_key_enabled() must return true, so return 1 here.
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*/
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int n = atomic_read(&key->enabled);
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return n >= 0 ? n : 1;
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}
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EXPORT_SYMBOL_GPL(static_key_count);
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void static_key_enable(struct static_key *key)
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{
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int count = static_key_count(key);
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WARN_ON_ONCE(count < 0 || count > 1);
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if (!count)
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static_key_slow_inc(key);
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}
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EXPORT_SYMBOL_GPL(static_key_enable);
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void static_key_disable(struct static_key *key)
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{
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int count = static_key_count(key);
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WARN_ON_ONCE(count < 0 || count > 1);
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if (count)
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static_key_slow_dec(key);
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}
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EXPORT_SYMBOL_GPL(static_key_disable);
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void static_key_slow_inc(struct static_key *key)
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{
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int v, v1;
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STATIC_KEY_CHECK_USE();
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/*
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* Careful if we get concurrent static_key_slow_inc() calls;
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* later calls must wait for the first one to _finish_ the
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* jump_label_update() process. At the same time, however,
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* the jump_label_update() call below wants to see
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* static_key_enabled(&key) for jumps to be updated properly.
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*
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* So give a special meaning to negative key->enabled: it sends
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* static_key_slow_inc() down the slow path, and it is non-zero
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* so it counts as "enabled" in jump_label_update(). Note that
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* atomic_inc_unless_negative() checks >= 0, so roll our own.
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*/
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for (v = atomic_read(&key->enabled); v > 0; v = v1) {
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v1 = atomic_cmpxchg(&key->enabled, v, v + 1);
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if (likely(v1 == v))
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return;
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}
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jump_label_lock();
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if (atomic_read(&key->enabled) == 0) {
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atomic_set(&key->enabled, -1);
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jump_label_update(key);
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atomic_set(&key->enabled, 1);
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} else {
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atomic_inc(&key->enabled);
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}
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jump_label_unlock();
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}
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EXPORT_SYMBOL_GPL(static_key_slow_inc);
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static void __static_key_slow_dec(struct static_key *key,
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unsigned long rate_limit, struct delayed_work *work)
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{
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/*
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* The negative count check is valid even when a negative
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* key->enabled is in use by static_key_slow_inc(); a
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* __static_key_slow_dec() before the first static_key_slow_inc()
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* returns is unbalanced, because all other static_key_slow_inc()
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* instances block while the update is in progress.
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*/
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if (!atomic_dec_and_mutex_lock(&key->enabled, &jump_label_mutex)) {
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WARN(atomic_read(&key->enabled) < 0,
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"jump label: negative count!\n");
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return;
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}
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if (rate_limit) {
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atomic_inc(&key->enabled);
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schedule_delayed_work(work, rate_limit);
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} else {
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jump_label_update(key);
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}
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jump_label_unlock();
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}
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static void jump_label_update_timeout(struct work_struct *work)
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{
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struct static_key_deferred *key =
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container_of(work, struct static_key_deferred, work.work);
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__static_key_slow_dec(&key->key, 0, NULL);
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}
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void static_key_slow_dec(struct static_key *key)
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{
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STATIC_KEY_CHECK_USE();
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__static_key_slow_dec(key, 0, NULL);
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}
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EXPORT_SYMBOL_GPL(static_key_slow_dec);
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void static_key_slow_dec_deferred(struct static_key_deferred *key)
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{
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STATIC_KEY_CHECK_USE();
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__static_key_slow_dec(&key->key, key->timeout, &key->work);
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}
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EXPORT_SYMBOL_GPL(static_key_slow_dec_deferred);
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void jump_label_rate_limit(struct static_key_deferred *key,
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unsigned long rl)
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{
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STATIC_KEY_CHECK_USE();
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key->timeout = rl;
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INIT_DELAYED_WORK(&key->work, jump_label_update_timeout);
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}
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EXPORT_SYMBOL_GPL(jump_label_rate_limit);
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static int addr_conflict(struct jump_entry *entry, void *start, void *end)
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{
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if (entry->code <= (unsigned long)end &&
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entry->code + JUMP_LABEL_NOP_SIZE > (unsigned long)start)
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return 1;
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return 0;
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}
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static int __jump_label_text_reserved(struct jump_entry *iter_start,
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struct jump_entry *iter_stop, void *start, void *end)
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{
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struct jump_entry *iter;
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iter = iter_start;
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while (iter < iter_stop) {
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if (addr_conflict(iter, start, end))
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return 1;
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iter++;
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}
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return 0;
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}
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/*
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* Update code which is definitely not currently executing.
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* Architectures which need heavyweight synchronization to modify
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* running code can override this to make the non-live update case
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* cheaper.
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*/
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void __weak __init_or_module arch_jump_label_transform_static(struct jump_entry *entry,
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enum jump_label_type type)
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{
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arch_jump_label_transform(entry, type);
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}
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static inline struct jump_entry *static_key_entries(struct static_key *key)
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{
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return (struct jump_entry *)((unsigned long)key->entries & ~JUMP_TYPE_MASK);
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}
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static inline bool static_key_type(struct static_key *key)
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{
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return (unsigned long)key->entries & JUMP_TYPE_MASK;
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}
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static inline struct static_key *jump_entry_key(struct jump_entry *entry)
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{
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return (struct static_key *)((unsigned long)entry->key & ~1UL);
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}
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static bool jump_entry_branch(struct jump_entry *entry)
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{
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return (unsigned long)entry->key & 1UL;
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}
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static enum jump_label_type jump_label_type(struct jump_entry *entry)
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{
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struct static_key *key = jump_entry_key(entry);
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bool enabled = static_key_enabled(key);
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bool branch = jump_entry_branch(entry);
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/* See the comment in linux/jump_label.h */
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return enabled ^ branch;
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}
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static void __jump_label_update(struct static_key *key,
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struct jump_entry *entry,
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struct jump_entry *stop)
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{
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for (; (entry < stop) && (jump_entry_key(entry) == key); entry++) {
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/*
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* entry->code set to 0 invalidates module init text sections
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* kernel_text_address() verifies we are not in core kernel
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* init code, see jump_label_invalidate_module_init().
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*/
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if (entry->code && kernel_text_address(entry->code))
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arch_jump_label_transform(entry, jump_label_type(entry));
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}
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}
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void __init jump_label_init(void)
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{
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struct jump_entry *iter_start = __start___jump_table;
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struct jump_entry *iter_stop = __stop___jump_table;
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struct static_key *key = NULL;
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struct jump_entry *iter;
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/*
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* Since we are initializing the static_key.enabled field with
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* with the 'raw' int values (to avoid pulling in atomic.h) in
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* jump_label.h, let's make sure that is safe. There are only two
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* cases to check since we initialize to 0 or 1.
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*/
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BUILD_BUG_ON((int)ATOMIC_INIT(0) != 0);
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BUILD_BUG_ON((int)ATOMIC_INIT(1) != 1);
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if (static_key_initialized)
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return;
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jump_label_lock();
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jump_label_sort_entries(iter_start, iter_stop);
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for (iter = iter_start; iter < iter_stop; iter++) {
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struct static_key *iterk;
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/* rewrite NOPs */
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if (jump_label_type(iter) == JUMP_LABEL_NOP)
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arch_jump_label_transform_static(iter, JUMP_LABEL_NOP);
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iterk = jump_entry_key(iter);
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if (iterk == key)
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continue;
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key = iterk;
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/*
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* Set key->entries to iter, but preserve JUMP_LABEL_TRUE_BRANCH.
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*/
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*((unsigned long *)&key->entries) += (unsigned long)iter;
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#ifdef CONFIG_MODULES
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key->next = NULL;
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#endif
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}
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static_key_initialized = true;
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jump_label_unlock();
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}
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#ifdef CONFIG_MODULES
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static enum jump_label_type jump_label_init_type(struct jump_entry *entry)
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{
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struct static_key *key = jump_entry_key(entry);
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bool type = static_key_type(key);
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bool branch = jump_entry_branch(entry);
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/* See the comment in linux/jump_label.h */
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return type ^ branch;
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}
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struct static_key_mod {
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struct static_key_mod *next;
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struct jump_entry *entries;
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struct module *mod;
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};
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static int __jump_label_mod_text_reserved(void *start, void *end)
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{
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struct module *mod;
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preempt_disable();
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mod = __module_text_address((unsigned long)start);
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WARN_ON_ONCE(__module_text_address((unsigned long)end) != mod);
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preempt_enable();
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if (!mod)
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return 0;
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return __jump_label_text_reserved(mod->jump_entries,
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mod->jump_entries + mod->num_jump_entries,
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start, end);
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}
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static void __jump_label_mod_update(struct static_key *key)
|
|
{
|
|
struct static_key_mod *mod;
|
|
|
|
for (mod = key->next; mod; mod = mod->next) {
|
|
struct module *m = mod->mod;
|
|
|
|
__jump_label_update(key, mod->entries,
|
|
m->jump_entries + m->num_jump_entries);
|
|
}
|
|
}
|
|
|
|
/***
|
|
* apply_jump_label_nops - patch module jump labels with arch_get_jump_label_nop()
|
|
* @mod: module to patch
|
|
*
|
|
* Allow for run-time selection of the optimal nops. Before the module
|
|
* loads patch these with arch_get_jump_label_nop(), which is specified by
|
|
* the arch specific jump label code.
|
|
*/
|
|
void jump_label_apply_nops(struct module *mod)
|
|
{
|
|
struct jump_entry *iter_start = mod->jump_entries;
|
|
struct jump_entry *iter_stop = iter_start + mod->num_jump_entries;
|
|
struct jump_entry *iter;
|
|
|
|
/* if the module doesn't have jump label entries, just return */
|
|
if (iter_start == iter_stop)
|
|
return;
|
|
|
|
for (iter = iter_start; iter < iter_stop; iter++) {
|
|
/* Only write NOPs for arch_branch_static(). */
|
|
if (jump_label_init_type(iter) == JUMP_LABEL_NOP)
|
|
arch_jump_label_transform_static(iter, JUMP_LABEL_NOP);
|
|
}
|
|
}
|
|
|
|
static int jump_label_add_module(struct module *mod)
|
|
{
|
|
struct jump_entry *iter_start = mod->jump_entries;
|
|
struct jump_entry *iter_stop = iter_start + mod->num_jump_entries;
|
|
struct jump_entry *iter;
|
|
struct static_key *key = NULL;
|
|
struct static_key_mod *jlm;
|
|
|
|
/* if the module doesn't have jump label entries, just return */
|
|
if (iter_start == iter_stop)
|
|
return 0;
|
|
|
|
jump_label_sort_entries(iter_start, iter_stop);
|
|
|
|
for (iter = iter_start; iter < iter_stop; iter++) {
|
|
struct static_key *iterk;
|
|
|
|
iterk = jump_entry_key(iter);
|
|
if (iterk == key)
|
|
continue;
|
|
|
|
key = iterk;
|
|
if (within_module(iter->key, mod)) {
|
|
/*
|
|
* Set key->entries to iter, but preserve JUMP_LABEL_TRUE_BRANCH.
|
|
*/
|
|
*((unsigned long *)&key->entries) += (unsigned long)iter;
|
|
key->next = NULL;
|
|
continue;
|
|
}
|
|
jlm = kzalloc(sizeof(struct static_key_mod), GFP_KERNEL);
|
|
if (!jlm)
|
|
return -ENOMEM;
|
|
jlm->mod = mod;
|
|
jlm->entries = iter;
|
|
jlm->next = key->next;
|
|
key->next = jlm;
|
|
|
|
/* Only update if we've changed from our initial state */
|
|
if (jump_label_type(iter) != jump_label_init_type(iter))
|
|
__jump_label_update(key, iter, iter_stop);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void jump_label_del_module(struct module *mod)
|
|
{
|
|
struct jump_entry *iter_start = mod->jump_entries;
|
|
struct jump_entry *iter_stop = iter_start + mod->num_jump_entries;
|
|
struct jump_entry *iter;
|
|
struct static_key *key = NULL;
|
|
struct static_key_mod *jlm, **prev;
|
|
|
|
for (iter = iter_start; iter < iter_stop; iter++) {
|
|
if (jump_entry_key(iter) == key)
|
|
continue;
|
|
|
|
key = jump_entry_key(iter);
|
|
|
|
if (within_module(iter->key, mod))
|
|
continue;
|
|
|
|
prev = &key->next;
|
|
jlm = key->next;
|
|
|
|
while (jlm && jlm->mod != mod) {
|
|
prev = &jlm->next;
|
|
jlm = jlm->next;
|
|
}
|
|
|
|
if (jlm) {
|
|
*prev = jlm->next;
|
|
kfree(jlm);
|
|
}
|
|
}
|
|
}
|
|
|
|
static void jump_label_invalidate_module_init(struct module *mod)
|
|
{
|
|
struct jump_entry *iter_start = mod->jump_entries;
|
|
struct jump_entry *iter_stop = iter_start + mod->num_jump_entries;
|
|
struct jump_entry *iter;
|
|
|
|
for (iter = iter_start; iter < iter_stop; iter++) {
|
|
if (within_module_init(iter->code, mod))
|
|
iter->code = 0;
|
|
}
|
|
}
|
|
|
|
static int
|
|
jump_label_module_notify(struct notifier_block *self, unsigned long val,
|
|
void *data)
|
|
{
|
|
struct module *mod = data;
|
|
int ret = 0;
|
|
|
|
switch (val) {
|
|
case MODULE_STATE_COMING:
|
|
jump_label_lock();
|
|
ret = jump_label_add_module(mod);
|
|
if (ret)
|
|
jump_label_del_module(mod);
|
|
jump_label_unlock();
|
|
break;
|
|
case MODULE_STATE_GOING:
|
|
jump_label_lock();
|
|
jump_label_del_module(mod);
|
|
jump_label_unlock();
|
|
break;
|
|
case MODULE_STATE_LIVE:
|
|
jump_label_lock();
|
|
jump_label_invalidate_module_init(mod);
|
|
jump_label_unlock();
|
|
break;
|
|
}
|
|
|
|
return notifier_from_errno(ret);
|
|
}
|
|
|
|
static struct notifier_block jump_label_module_nb = {
|
|
.notifier_call = jump_label_module_notify,
|
|
.priority = 1, /* higher than tracepoints */
|
|
};
|
|
|
|
static __init int jump_label_init_module(void)
|
|
{
|
|
return register_module_notifier(&jump_label_module_nb);
|
|
}
|
|
early_initcall(jump_label_init_module);
|
|
|
|
#endif /* CONFIG_MODULES */
|
|
|
|
/***
|
|
* jump_label_text_reserved - check if addr range is reserved
|
|
* @start: start text addr
|
|
* @end: end text addr
|
|
*
|
|
* checks if the text addr located between @start and @end
|
|
* overlaps with any of the jump label patch addresses. Code
|
|
* that wants to modify kernel text should first verify that
|
|
* it does not overlap with any of the jump label addresses.
|
|
* Caller must hold jump_label_mutex.
|
|
*
|
|
* returns 1 if there is an overlap, 0 otherwise
|
|
*/
|
|
int jump_label_text_reserved(void *start, void *end)
|
|
{
|
|
int ret = __jump_label_text_reserved(__start___jump_table,
|
|
__stop___jump_table, start, end);
|
|
|
|
if (ret)
|
|
return ret;
|
|
|
|
#ifdef CONFIG_MODULES
|
|
ret = __jump_label_mod_text_reserved(start, end);
|
|
#endif
|
|
return ret;
|
|
}
|
|
|
|
static void jump_label_update(struct static_key *key)
|
|
{
|
|
struct jump_entry *stop = __stop___jump_table;
|
|
struct jump_entry *entry = static_key_entries(key);
|
|
#ifdef CONFIG_MODULES
|
|
struct module *mod;
|
|
|
|
__jump_label_mod_update(key);
|
|
|
|
preempt_disable();
|
|
mod = __module_address((unsigned long)key);
|
|
if (mod)
|
|
stop = mod->jump_entries + mod->num_jump_entries;
|
|
preempt_enable();
|
|
#endif
|
|
/* if there are no users, entry can be NULL */
|
|
if (entry)
|
|
__jump_label_update(key, entry, stop);
|
|
}
|
|
|
|
#ifdef CONFIG_STATIC_KEYS_SELFTEST
|
|
static DEFINE_STATIC_KEY_TRUE(sk_true);
|
|
static DEFINE_STATIC_KEY_FALSE(sk_false);
|
|
|
|
static __init int jump_label_test(void)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < 2; i++) {
|
|
WARN_ON(static_key_enabled(&sk_true.key) != true);
|
|
WARN_ON(static_key_enabled(&sk_false.key) != false);
|
|
|
|
WARN_ON(!static_branch_likely(&sk_true));
|
|
WARN_ON(!static_branch_unlikely(&sk_true));
|
|
WARN_ON(static_branch_likely(&sk_false));
|
|
WARN_ON(static_branch_unlikely(&sk_false));
|
|
|
|
static_branch_disable(&sk_true);
|
|
static_branch_enable(&sk_false);
|
|
|
|
WARN_ON(static_key_enabled(&sk_true.key) == true);
|
|
WARN_ON(static_key_enabled(&sk_false.key) == false);
|
|
|
|
WARN_ON(static_branch_likely(&sk_true));
|
|
WARN_ON(static_branch_unlikely(&sk_true));
|
|
WARN_ON(!static_branch_likely(&sk_false));
|
|
WARN_ON(!static_branch_unlikely(&sk_false));
|
|
|
|
static_branch_enable(&sk_true);
|
|
static_branch_disable(&sk_false);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
late_initcall(jump_label_test);
|
|
#endif /* STATIC_KEYS_SELFTEST */
|
|
|
|
#endif /* HAVE_JUMP_LABEL */
|