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-rw-r--r--lib/Kconfig.debug15
-rw-r--r--lib/Kconfig.kasan98
-rw-r--r--lib/debugobjects.c8
-rw-r--r--lib/ioremap.c103
-rw-r--r--lib/show_mem.c5
5 files changed, 166 insertions, 63 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index b3c91b9e32f8..2b5a4256e88b 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -593,6 +593,21 @@ config DEBUG_KMEMLEAK_DEFAULT_OFF
Say Y here to disable kmemleak by default. It can then be enabled
on the command line via kmemleak=on.
+config DEBUG_KMEMLEAK_AUTO_SCAN
+ bool "Enable kmemleak auto scan thread on boot up"
+ default y
+ depends on DEBUG_KMEMLEAK
+ help
+ Depending on the cpu, kmemleak scan may be cpu intensive and can
+ stall user tasks at times. This option enables/disables automatic
+ kmemleak scan at boot up.
+
+ Say N here to disable kmemleak auto scan thread to stop automatic
+ scanning. Disabling this option disables automatic reporting of
+ memory leaks.
+
+ If unsure, say Y.
+
config DEBUG_STACK_USAGE
bool "Stack utilization instrumentation"
depends on DEBUG_KERNEL && !IA64
diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan
index d0bad1bd9a2b..d8c474b6691e 100644
--- a/lib/Kconfig.kasan
+++ b/lib/Kconfig.kasan
@@ -1,36 +1,92 @@
+# This config refers to the generic KASAN mode.
config HAVE_ARCH_KASAN
bool
-if HAVE_ARCH_KASAN
+config HAVE_ARCH_KASAN_SW_TAGS
+ bool
+
+config CC_HAS_KASAN_GENERIC
+ def_bool $(cc-option, -fsanitize=kernel-address)
+
+config CC_HAS_KASAN_SW_TAGS
+ def_bool $(cc-option, -fsanitize=kernel-hwaddress)
config KASAN
- bool "KASan: runtime memory debugger"
+ bool "KASAN: runtime memory debugger"
+ depends on (HAVE_ARCH_KASAN && CC_HAS_KASAN_GENERIC) || \
+ (HAVE_ARCH_KASAN_SW_TAGS && CC_HAS_KASAN_SW_TAGS)
+ depends on (SLUB && SYSFS) || (SLAB && !DEBUG_SLAB)
+ help
+ Enables KASAN (KernelAddressSANitizer) - runtime memory debugger,
+ designed to find out-of-bounds accesses and use-after-free bugs.
+ See Documentation/dev-tools/kasan.rst for details.
+
+choice
+ prompt "KASAN mode"
+ depends on KASAN
+ default KASAN_GENERIC
+ help
+ KASAN has two modes: generic KASAN (similar to userspace ASan,
+ x86_64/arm64/xtensa, enabled with CONFIG_KASAN_GENERIC) and
+ software tag-based KASAN (a version based on software memory
+ tagging, arm64 only, similar to userspace HWASan, enabled with
+ CONFIG_KASAN_SW_TAGS).
+ Both generic and tag-based KASAN are strictly debugging features.
+
+config KASAN_GENERIC
+ bool "Generic mode"
+ depends on HAVE_ARCH_KASAN && CC_HAS_KASAN_GENERIC
depends on (SLUB && SYSFS) || (SLAB && !DEBUG_SLAB)
select SLUB_DEBUG if SLUB
select CONSTRUCTORS
select STACKDEPOT
help
- Enables kernel address sanitizer - runtime memory debugger,
- designed to find out-of-bounds accesses and use-after-free bugs.
- This is strictly a debugging feature and it requires a gcc version
- of 4.9.2 or later. Detection of out of bounds accesses to stack or
- global variables requires gcc 5.0 or later.
- This feature consumes about 1/8 of available memory and brings about
- ~x3 performance slowdown.
+ Enables generic KASAN mode.
+ Supported in both GCC and Clang. With GCC it requires version 4.9.2
+ or later for basic support and version 5.0 or later for detection of
+ out-of-bounds accesses for stack and global variables and for inline
+ instrumentation mode (CONFIG_KASAN_INLINE). With Clang it requires
+ version 3.7.0 or later and it doesn't support detection of
+ out-of-bounds accesses for global variables yet.
+ This mode consumes about 1/8th of available memory at kernel start
+ and introduces an overhead of ~x1.5 for the rest of the allocations.
+ The performance slowdown is ~x3.
For better error detection enable CONFIG_STACKTRACE.
- Currently CONFIG_KASAN doesn't work with CONFIG_DEBUG_SLAB
+ Currently CONFIG_KASAN_GENERIC doesn't work with CONFIG_DEBUG_SLAB
(the resulting kernel does not boot).
+config KASAN_SW_TAGS
+ bool "Software tag-based mode"
+ depends on HAVE_ARCH_KASAN_SW_TAGS && CC_HAS_KASAN_SW_TAGS
+ depends on (SLUB && SYSFS) || (SLAB && !DEBUG_SLAB)
+ select SLUB_DEBUG if SLUB
+ select CONSTRUCTORS
+ select STACKDEPOT
+ help
+ Enables software tag-based KASAN mode.
+ This mode requires Top Byte Ignore support by the CPU and therefore
+ is only supported for arm64.
+ This mode requires Clang version 7.0.0 or later.
+ This mode consumes about 1/16th of available memory at kernel start
+ and introduces an overhead of ~20% for the rest of the allocations.
+ This mode may potentially introduce problems relating to pointer
+ casting and comparison, as it embeds tags into the top byte of each
+ pointer.
+ For better error detection enable CONFIG_STACKTRACE.
+ Currently CONFIG_KASAN_SW_TAGS doesn't work with CONFIG_DEBUG_SLAB
+ (the resulting kernel does not boot).
+
+endchoice
+
config KASAN_EXTRA
- bool "KAsan: extra checks"
- depends on KASAN && DEBUG_KERNEL && !COMPILE_TEST
+ bool "KASAN: extra checks"
+ depends on KASAN_GENERIC && DEBUG_KERNEL && !COMPILE_TEST
help
- This enables further checks in the kernel address sanitizer, for now
- it only includes the address-use-after-scope check that can lead
- to excessive kernel stack usage, frame size warnings and longer
+ This enables further checks in generic KASAN, for now it only
+ includes the address-use-after-scope check that can lead to
+ excessive kernel stack usage, frame size warnings and longer
compile time.
- https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715 has more
-
+ See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715
choice
prompt "Instrumentation type"
@@ -53,7 +109,7 @@ config KASAN_INLINE
memory accesses. This is faster than outline (in some workloads
it gives about x2 boost over outline instrumentation), but
make kernel's .text size much bigger.
- This requires a gcc version of 5.0 or later.
+ For CONFIG_KASAN_GENERIC this requires GCC 5.0 or later.
endchoice
@@ -67,11 +123,9 @@ config KASAN_S390_4_LEVEL_PAGING
4-level paging instead.
config TEST_KASAN
- tristate "Module for testing kasan for bug detection"
+ tristate "Module for testing KASAN for bug detection"
depends on m && KASAN
help
This is a test module doing various nasty things like
out of bounds accesses, use after free. It is useful for testing
- kernel debugging features like kernel address sanitizer.
-
-endif
+ kernel debugging features like KASAN.
diff --git a/lib/debugobjects.c b/lib/debugobjects.c
index 14afeeb7d6ef..55437fd5128b 100644
--- a/lib/debugobjects.c
+++ b/lib/debugobjects.c
@@ -1131,11 +1131,10 @@ static int __init debug_objects_replace_static_objects(void)
}
/*
- * When debug_objects_mem_init() is called we know that only
- * one CPU is up, so disabling interrupts is enough
- * protection. This avoids the lockdep hell of lock ordering.
+ * debug_objects_mem_init() is now called early that only one CPU is up
+ * and interrupts have been disabled, so it is safe to replace the
+ * active object references.
*/
- local_irq_disable();
/* Remove the statically allocated objects from the pool */
hlist_for_each_entry_safe(obj, tmp, &obj_pool, node)
@@ -1156,7 +1155,6 @@ static int __init debug_objects_replace_static_objects(void)
cnt++;
}
}
- local_irq_enable();
pr_debug("%d of %d active objects replaced\n",
cnt, obj_pool_used);
diff --git a/lib/ioremap.c b/lib/ioremap.c
index 517f5853ffed..063213685563 100644
--- a/lib/ioremap.c
+++ b/lib/ioremap.c
@@ -76,83 +76,123 @@ static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
return 0;
}
+static int ioremap_try_huge_pmd(pmd_t *pmd, unsigned long addr,
+ unsigned long end, phys_addr_t phys_addr,
+ pgprot_t prot)
+{
+ if (!ioremap_pmd_enabled())
+ return 0;
+
+ if ((end - addr) != PMD_SIZE)
+ return 0;
+
+ if (!IS_ALIGNED(phys_addr, PMD_SIZE))
+ return 0;
+
+ if (pmd_present(*pmd) && !pmd_free_pte_page(pmd, addr))
+ return 0;
+
+ return pmd_set_huge(pmd, phys_addr, prot);
+}
+
static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr,
unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
{
pmd_t *pmd;
unsigned long next;
- phys_addr -= addr;
pmd = pmd_alloc(&init_mm, pud, addr);
if (!pmd)
return -ENOMEM;
do {
next = pmd_addr_end(addr, end);
- if (ioremap_pmd_enabled() &&
- ((next - addr) == PMD_SIZE) &&
- IS_ALIGNED(phys_addr + addr, PMD_SIZE) &&
- pmd_free_pte_page(pmd, addr)) {
- if (pmd_set_huge(pmd, phys_addr + addr, prot))
- continue;
- }
+ if (ioremap_try_huge_pmd(pmd, addr, next, phys_addr, prot))
+ continue;
- if (ioremap_pte_range(pmd, addr, next, phys_addr + addr, prot))
+ if (ioremap_pte_range(pmd, addr, next, phys_addr, prot))
return -ENOMEM;
- } while (pmd++, addr = next, addr != end);
+ } while (pmd++, phys_addr += (next - addr), addr = next, addr != end);
return 0;
}
+static int ioremap_try_huge_pud(pud_t *pud, unsigned long addr,
+ unsigned long end, phys_addr_t phys_addr,
+ pgprot_t prot)
+{
+ if (!ioremap_pud_enabled())
+ return 0;
+
+ if ((end - addr) != PUD_SIZE)
+ return 0;
+
+ if (!IS_ALIGNED(phys_addr, PUD_SIZE))
+ return 0;
+
+ if (pud_present(*pud) && !pud_free_pmd_page(pud, addr))
+ return 0;
+
+ return pud_set_huge(pud, phys_addr, prot);
+}
+
static inline int ioremap_pud_range(p4d_t *p4d, unsigned long addr,
unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
{
pud_t *pud;
unsigned long next;
- phys_addr -= addr;
pud = pud_alloc(&init_mm, p4d, addr);
if (!pud)
return -ENOMEM;
do {
next = pud_addr_end(addr, end);
- if (ioremap_pud_enabled() &&
- ((next - addr) == PUD_SIZE) &&
- IS_ALIGNED(phys_addr + addr, PUD_SIZE) &&
- pud_free_pmd_page(pud, addr)) {
- if (pud_set_huge(pud, phys_addr + addr, prot))
- continue;
- }
+ if (ioremap_try_huge_pud(pud, addr, next, phys_addr, prot))
+ continue;
- if (ioremap_pmd_range(pud, addr, next, phys_addr + addr, prot))
+ if (ioremap_pmd_range(pud, addr, next, phys_addr, prot))
return -ENOMEM;
- } while (pud++, addr = next, addr != end);
+ } while (pud++, phys_addr += (next - addr), addr = next, addr != end);
return 0;
}
+static int ioremap_try_huge_p4d(p4d_t *p4d, unsigned long addr,
+ unsigned long end, phys_addr_t phys_addr,
+ pgprot_t prot)
+{
+ if (!ioremap_p4d_enabled())
+ return 0;
+
+ if ((end - addr) != P4D_SIZE)
+ return 0;
+
+ if (!IS_ALIGNED(phys_addr, P4D_SIZE))
+ return 0;
+
+ if (p4d_present(*p4d) && !p4d_free_pud_page(p4d, addr))
+ return 0;
+
+ return p4d_set_huge(p4d, phys_addr, prot);
+}
+
static inline int ioremap_p4d_range(pgd_t *pgd, unsigned long addr,
unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
{
p4d_t *p4d;
unsigned long next;
- phys_addr -= addr;
p4d = p4d_alloc(&init_mm, pgd, addr);
if (!p4d)
return -ENOMEM;
do {
next = p4d_addr_end(addr, end);
- if (ioremap_p4d_enabled() &&
- ((next - addr) == P4D_SIZE) &&
- IS_ALIGNED(phys_addr + addr, P4D_SIZE)) {
- if (p4d_set_huge(p4d, phys_addr + addr, prot))
- continue;
- }
+ if (ioremap_try_huge_p4d(p4d, addr, next, phys_addr, prot))
+ continue;
- if (ioremap_pud_range(p4d, addr, next, phys_addr + addr, prot))
+ if (ioremap_pud_range(p4d, addr, next, phys_addr, prot))
return -ENOMEM;
- } while (p4d++, addr = next, addr != end);
+ } while (p4d++, phys_addr += (next - addr), addr = next, addr != end);
return 0;
}
@@ -168,14 +208,13 @@ int ioremap_page_range(unsigned long addr,
BUG_ON(addr >= end);
start = addr;
- phys_addr -= addr;
pgd = pgd_offset_k(addr);
do {
next = pgd_addr_end(addr, end);
- err = ioremap_p4d_range(pgd, addr, next, phys_addr+addr, prot);
+ err = ioremap_p4d_range(pgd, addr, next, phys_addr, prot);
if (err)
break;
- } while (pgd++, addr = next, addr != end);
+ } while (pgd++, phys_addr += (next - addr), addr = next, addr != end);
flush_cache_vmap(start, end);
diff --git a/lib/show_mem.c b/lib/show_mem.c
index 0beaa1d899aa..6a042f53e7bb 100644
--- a/lib/show_mem.c
+++ b/lib/show_mem.c
@@ -18,22 +18,19 @@ void show_mem(unsigned int filter, nodemask_t *nodemask)
show_free_areas(filter, nodemask);
for_each_online_pgdat(pgdat) {
- unsigned long flags;
int zoneid;
- pgdat_resize_lock(pgdat, &flags);
for (zoneid = 0; zoneid < MAX_NR_ZONES; zoneid++) {
struct zone *zone = &pgdat->node_zones[zoneid];
if (!populated_zone(zone))
continue;
total += zone->present_pages;
- reserved += zone->present_pages - zone->managed_pages;
+ reserved += zone->present_pages - zone_managed_pages(zone);
if (is_highmem_idx(zoneid))
highmem += zone->present_pages;
}
- pgdat_resize_unlock(pgdat, &flags);
}
printk("%lu pages RAM\n", total);
generated by cgit v1.2.3-58-ga151 (git 2.39.0) at 2024-12-04 04:24:08 +0000