From: "Mike Rapoport (IBM)"
Extend execmem parameters to accommodate more complex overrides of
module_alloc() by architectures.
This includes specification of a fallback range required by arm, arm64
and powerpc, EXECMEM_MODULE_DATA type required by powerpc, support for
allocation of KASAN shadow required by s390 and x86 and support for
late initialization of execmem required by arm64.
The core implementation of execmem_alloc() takes care of suppressing
warnings when the initial allocation fails but there is a fallback range
defined.
Signed-off-by: Mike Rapoport (IBM)
Acked-by: Will Deacon
---
arch/Kconfig | 8
arch/arm/kernel/module.c | 41
arch/arm64/Kconfig | 1 +
arch/arm64/kernel/module.c | 55 ++
arch/powerpc/kernel/module.c | 60 +++--
arch/s390/kernel/module.c| 54 +++---
arch/x86/kernel/module.c | 70 +++--
include/linux/execmem.h | 30 ++-
include/linux/moduleloader.h | 12 --
kernel/module/main.c | 26 +++--
mm/execmem.c | 75 ++--
11 files changed, 247 insertions(+), 185 deletions(-)
diff --git a/arch/Kconfig b/arch/Kconfig
index 65afb1de48b3..4fd0daa54e6c 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -960,6 +960,14 @@ config ARCH_WANTS_MODULES_DATA_IN_VMALLOC
For architectures like powerpc/32 which have constraints on module
allocation and need to allocate module data outside of module area.
+config ARCH_WANTS_EXECMEM_LATE
+ bool
+ help
+ For architectures that do not allocate executable memory early on
+ boot, but rather require its initialization late when there is
+ enough entropy for module space randomization, for instance
+ arm64.
+
config HAVE_IRQ_EXIT_ON_IRQ_STACK
bool
help
diff --git a/arch/arm/kernel/module.c b/arch/arm/kernel/module.c
index e74d84f58b77..a98fdf6ff26c 100644
--- a/arch/arm/kernel/module.c
+++ b/arch/arm/kernel/module.c
@@ -16,6 +16,7 @@
#include
#include
#include
+#include
#include
#include
@@ -34,23 +35,31 @@
#endif
#ifdef CONFIG_MMU
-void *module_alloc(unsigned long size)
+static struct execmem_info execmem_info __ro_after_init;
+
+struct execmem_info __init *execmem_arch_setup(void)
{
- gfp_t gfp_mask = GFP_KERNEL;
- void *p;
-
- /* Silence the initial allocation */
- if (IS_ENABLED(CONFIG_ARM_MODULE_PLTS))
- gfp_mask |= __GFP_NOWARN;
-
- p = __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
- gfp_mask, PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE,
- __builtin_return_address(0));
- if (!IS_ENABLED(CONFIG_ARM_MODULE_PLTS) || p)
- return p;
- return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END,
- GFP_KERNEL, PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE,
- __builtin_return_address(0));
+ unsigned long fallback_start = 0, fallback_end = 0;
+
+ if (IS_ENABLED(CONFIG_ARM_MODULE_PLTS)) {
+ fallback_start = VMALLOC_START;
+ fallback_end = VMALLOC_END;
+ }
+
+ execmem_info = (struct execmem_info){
+ .ranges = {
+ [EXECMEM_DEFAULT] = {
+ .start = MODULES_VADDR,
+ .end= MODULES_END,
+ .pgprot = PAGE_KERNEL_EXEC,
+ .alignment = 1,
+ .fallback_start = fallback_start,
+ .fallback_end = fallback_end,
+ },
+ },
+ };
+
+ return &execmem_info;
}
#endif
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 7b11c98b3e84..74b34a78b7ac 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -105,6 +105,7 @@ config ARM64
select ARCH_WANT_FRAME_POINTERS
select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES
&& !ARM64_VA_BITS_36)
select ARCH_WANT_LD_ORPHAN_WARN
+ select ARCH_WANTS_EXECMEM_LATE if EXECMEM
select ARCH_WANTS_NO_INSTR
select ARCH_WANTS_THP_SWAP if ARM64_4K_PAGES
select ARCH_HAS_UBSAN
diff --git a/arch/arm64/kernel/module.c b/arch/arm64/kernel/module.c
index e92da4da1b2a..b7a7a23f9f8f 100644
--- a/arch/arm64/kernel/module.c
+++ b/arch/arm64/kernel/module.c
@@ -20,6 +20,7 @@
#include
#include
#include
+#include
#include
#include
@@ -108,41 +109,47 @@ static int __init module_init_limits(void)
return 0;
}
-subsys_initcall(module_init_limits);
-void *module_alloc(unsigned long size)
+static struct execmem_info execmem_info __ro_after_init;
+
+struct execmem_info __init *execmem_arch_setup(void)
{
- void *p = NU