Le 29/04/2021 à 05:15, Jordan Niethe a écrit :
If MODULES_{VADDR,END} are not defined set them to VMALLOC_START and
VMALLOC_END respectively. This reduces the need for special cases. For
example, powerpc's module_alloc() was previously predicated on
MODULES_VADDR being defined but now is unconditionally defined.
This will be useful reducing conditional code in other places that need
to allocate from the module region (i.e., kprobes).
Signed-off-by: Jordan Niethe <jniet...@gmail.com>
---
v10: New to series
v11: - Consider more places MODULES_VADDR was being used
---
arch/powerpc/include/asm/pgtable.h | 11 +++++++++++
arch/powerpc/kernel/module.c | 5 +----
arch/powerpc/mm/kasan/kasan_init_32.c | 10 +++++-----
arch/powerpc/mm/ptdump/ptdump.c | 4 ++--
4 files changed, 19 insertions(+), 11 deletions(-)
diff --git a/arch/powerpc/include/asm/pgtable.h
b/arch/powerpc/include/asm/pgtable.h
index c6a676714f04..882fda779648 100644
--- a/arch/powerpc/include/asm/pgtable.h
+++ b/arch/powerpc/include/asm/pgtable.h
@@ -39,6 +39,17 @@ struct mm_struct;
#define __S110 PAGE_SHARED_X
#define __S111 PAGE_SHARED_X
+#ifndef MODULES_VADDR
+#define MODULES_VADDR VMALLOC_START
+#define MODULES_END VMALLOC_END
+#endif
+
+#if defined(CONFIG_PPC_BOOK3S_32) && defined(CONFIG_STRICT_KERNEL_RWX)
No no.
TASK_SIZE > MODULES_VADDR is ALWAYS wrong, for any target, in any configuration.
Why is it a problem to leave the test as a BUILD_BUG_ON() in module_alloc() ?
+#if TASK_SIZE > MODULES_VADDR
+#error TASK_SIZE > MODULES_VADDR
+#endif
+#endif
+
#ifndef __ASSEMBLY__
/* Keep these as a macros to avoid include dependency mess */
diff --git a/arch/powerpc/kernel/module.c b/arch/powerpc/kernel/module.c
index fab84024650c..c60c7457ff47 100644
--- a/arch/powerpc/kernel/module.c
+++ b/arch/powerpc/kernel/module.c
@@ -15,6 +15,7 @@
#include <linux/sort.h>
#include <asm/setup.h>
#include <asm/sections.h>
+#include <linux/mm.h>
static LIST_HEAD(module_bug_list);
@@ -88,7 +89,6 @@ int module_finalize(const Elf_Ehdr *hdr,
return 0;
}
-#ifdef MODULES_VADDR
static __always_inline void *
__module_alloc(unsigned long size, unsigned long start, unsigned long end)
{
@@ -102,8 +102,6 @@ void *module_alloc(unsigned long size)
unsigned long limit = (unsigned long)_etext - SZ_32M;
void *ptr = NULL;
- BUILD_BUG_ON(TASK_SIZE > MODULES_VADDR);
-
/* First try within 32M limit from _etext to avoid branch trampolines */
if (MODULES_VADDR < PAGE_OFFSET && MODULES_END > limit)
ptr = __module_alloc(size, limit, MODULES_END);
@@ -113,4 +111,3 @@ void *module_alloc(unsigned long size)
return ptr;
}
-#endif
diff --git a/arch/powerpc/mm/kasan/kasan_init_32.c
b/arch/powerpc/mm/kasan/kasan_init_32.c
index cf8770b1a692..42c057366ac7 100644
--- a/arch/powerpc/mm/kasan/kasan_init_32.c
+++ b/arch/powerpc/mm/kasan/kasan_init_32.c
@@ -116,11 +116,11 @@ static void __init kasan_unmap_early_shadow_vmalloc(void)
kasan_update_early_region(k_start, k_end, __pte(0));
-#ifdef MODULES_VADDR
- k_start = (unsigned long)kasan_mem_to_shadow((void *)MODULES_VADDR);
- k_end = (unsigned long)kasan_mem_to_shadow((void *)MODULES_END);
- kasan_update_early_region(k_start, k_end, __pte(0));
-#endif
+ if (MODULES_VADDR != VMALLOC_START && MODULES_END != VMALLOC_END) {
Shouldn't it be an || ?
As soon as either MODULES_VADDR or MODULES_END differs from the vmalloc boundaries, it needs to be
done I think.
+ k_start = (unsigned long)kasan_mem_to_shadow((void
*)MODULES_VADDR);
+ k_end = (unsigned long)kasan_mem_to_shadow((void *)MODULES_END);
+ kasan_update_early_region(k_start, k_end, __pte(0));
+ }
}
void __init kasan_mmu_init(void)
diff --git a/arch/powerpc/mm/ptdump/ptdump.c b/arch/powerpc/mm/ptdump/ptdump.c
index aca354fb670b..0431457f668f 100644
--- a/arch/powerpc/mm/ptdump/ptdump.c
+++ b/arch/powerpc/mm/ptdump/ptdump.c
@@ -73,7 +73,7 @@ struct addr_marker {
static struct addr_marker address_markers[] = {
{ 0, "Start of kernel VM" },
-#ifdef MODULES_VADDR
+#if defined(CONFIG_BOOK32_32) && defined(CONFIG_STRICT_KERNEL_RWX)
Not valid anymore, see https://github.com/linuxppc/linux/commit/80edc68e0479 and
https://github.com/linuxppc/linux/commit/9132a2e82adc
The best would be to be able to do something like:
#if MODULES_VADDR != VMALLOC_START
If it doesn't work, then it has to be
#if defined(CONFIG_BOOK32_32) || defined(CONFIG_PPC_8xx)
{ 0, "modules start" },
{ 0, "modules end" },
#endif
@@ -359,7 +359,7 @@ static void populate_markers(void)
#else
address_markers[i++].start_address = TASK_SIZE;
#endif
-#ifdef MODULES_VADDR
+#if defined(CONFIG_BOOK32_32) && defined(CONFIG_STRICT_KERNEL_RWX)
Same.
address_markers[i++].start_address = MODULES_VADDR;
address_markers[i++].start_address = MODULES_END;
#endif
