* [PATCH v2 1/3] powerpc/code-patching: Improve verification of patchability
@ 2021-09-25 8:31 ` Christophe Leroy
0 siblings, 0 replies; 6+ messages in thread
From: Christophe Leroy @ 2021-09-25 8:31 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: Christophe Leroy, linux-kernel, linuxppc-dev, Michael Neuling
Today, patch_instruction() assumes that is called exclusively on valid
addresses, and only checks that it is not called on an init address
after init section has been freed.
Improve verification by calling kernel_text_address() instead.
kernel_text_address() already includes a verification of
initmem release.
Cc: Michael Neuling <mikey@neuling.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/lib/code-patching.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c
index f9a3019e37b4..20ec6648aacc 100644
--- a/arch/powerpc/lib/code-patching.c
+++ b/arch/powerpc/lib/code-patching.c
@@ -190,10 +190,9 @@ static int do_patch_instruction(u32 *addr, struct ppc_inst instr)
int patch_instruction(u32 *addr, struct ppc_inst instr)
{
/* Make sure we aren't patching a freed init section */
- if (init_mem_is_free && init_section_contains(addr, 4)) {
- pr_debug("Skipping init section patching addr: 0x%px\n", addr);
+ if (!kernel_text_address((unsigned long)addr))
return 0;
- }
+
return do_patch_instruction(addr, instr);
}
NOKPROBE_SYMBOL(patch_instruction);
--
2.31.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v2 1/3] powerpc/code-patching: Improve verification of patchability
@ 2021-09-25 8:31 ` Christophe Leroy
0 siblings, 0 replies; 6+ messages in thread
From: Christophe Leroy @ 2021-09-25 8:31 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: Michael Neuling, linuxppc-dev, linux-kernel
Today, patch_instruction() assumes that is called exclusively on valid
addresses, and only checks that it is not called on an init address
after init section has been freed.
Improve verification by calling kernel_text_address() instead.
kernel_text_address() already includes a verification of
initmem release.
Cc: Michael Neuling <mikey@neuling.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/lib/code-patching.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c
index f9a3019e37b4..20ec6648aacc 100644
--- a/arch/powerpc/lib/code-patching.c
+++ b/arch/powerpc/lib/code-patching.c
@@ -190,10 +190,9 @@ static int do_patch_instruction(u32 *addr, struct ppc_inst instr)
int patch_instruction(u32 *addr, struct ppc_inst instr)
{
/* Make sure we aren't patching a freed init section */
- if (init_mem_is_free && init_section_contains(addr, 4)) {
- pr_debug("Skipping init section patching addr: 0x%px\n", addr);
+ if (!kernel_text_address((unsigned long)addr))
return 0;
- }
+
return do_patch_instruction(addr, instr);
}
NOKPROBE_SYMBOL(patch_instruction);
--
2.31.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v2 2/3] powerpc: Stop using init_mem_is_free
2021-09-25 8:31 ` Christophe Leroy
@ 2021-09-25 8:31 ` Christophe Leroy
-1 siblings, 0 replies; 6+ messages in thread
From: Christophe Leroy @ 2021-09-25 8:31 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: Christophe Leroy, linux-kernel, linuxppc-dev, Michael Neuling
Generic parts of the kernel for instance core_kernel_text()
use 'system_state' to check whether init memory has been
freed.
Do the same and stop using init_mem_is_free.
Cc: Michael Neuling <mikey@neuling.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch_is_kernel_initmem_freed() is likely going to go away via the mm tree, in that case this patch will void.
v2: Also remove declaration of init_mem_is_free.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/include/asm/sections.h | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/arch/powerpc/include/asm/sections.h b/arch/powerpc/include/asm/sections.h
index 6e4af4492a14..454b8434bfc4 100644
--- a/arch/powerpc/include/asm/sections.h
+++ b/arch/powerpc/include/asm/sections.h
@@ -10,11 +10,9 @@
#include <asm-generic/sections.h>
-extern bool init_mem_is_free;
-
static inline int arch_is_kernel_initmem_freed(unsigned long addr)
{
- if (!init_mem_is_free)
+ if (system_state < SYSTEM_RUNNING)
return 0;
return addr >= (unsigned long)__init_begin &&
--
2.31.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v2 2/3] powerpc: Stop using init_mem_is_free
@ 2021-09-25 8:31 ` Christophe Leroy
0 siblings, 0 replies; 6+ messages in thread
From: Christophe Leroy @ 2021-09-25 8:31 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: Michael Neuling, linuxppc-dev, linux-kernel
Generic parts of the kernel for instance core_kernel_text()
use 'system_state' to check whether init memory has been
freed.
Do the same and stop using init_mem_is_free.
Cc: Michael Neuling <mikey@neuling.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch_is_kernel_initmem_freed() is likely going to go away via the mm tree, in that case this patch will void.
v2: Also remove declaration of init_mem_is_free.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/include/asm/sections.h | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/arch/powerpc/include/asm/sections.h b/arch/powerpc/include/asm/sections.h
index 6e4af4492a14..454b8434bfc4 100644
--- a/arch/powerpc/include/asm/sections.h
+++ b/arch/powerpc/include/asm/sections.h
@@ -10,11 +10,9 @@
#include <asm-generic/sections.h>
-extern bool init_mem_is_free;
-
static inline int arch_is_kernel_initmem_freed(unsigned long addr)
{
- if (!init_mem_is_free)
+ if (system_state < SYSTEM_RUNNING)
return 0;
return addr >= (unsigned long)__init_begin &&
--
2.31.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH v2 3/3] powerpc: Remove init_mem_is_free
2021-09-25 8:31 ` Christophe Leroy
@ 2021-09-25 8:31 ` Christophe Leroy
-1 siblings, 0 replies; 6+ messages in thread
From: Christophe Leroy @ 2021-09-25 8:31 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: Christophe Leroy, linux-kernel, linuxppc-dev, Michael Neuling
init_mem_is_free is not used anymore. Remove it.
Cc: Michael Neuling <mikey@neuling.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/include/asm/setup.h | 1 -
arch/powerpc/mm/mem.c | 2 --
2 files changed, 3 deletions(-)
diff --git a/arch/powerpc/include/asm/setup.h b/arch/powerpc/include/asm/setup.h
index 6c1a7d217d1a..426a2d8d028f 100644
--- a/arch/powerpc/include/asm/setup.h
+++ b/arch/powerpc/include/asm/setup.h
@@ -9,7 +9,6 @@ extern void ppc_printk_progress(char *s, unsigned short hex);
extern unsigned int rtas_data;
extern unsigned long long memory_limit;
-extern bool init_mem_is_free;
extern void *zalloc_maybe_bootmem(size_t size, gfp_t mask);
struct device_node;
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index c3c4e31462ec..5b1eae6c0356 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -26,7 +26,6 @@
#include <mm/mmu_decl.h>
unsigned long long memory_limit;
-bool init_mem_is_free;
unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
EXPORT_SYMBOL(empty_zero_page);
@@ -312,7 +311,6 @@ void free_initmem(void)
{
ppc_md.progress = ppc_printk_progress;
mark_initmem_nx();
- init_mem_is_free = true;
free_initmem_default(POISON_FREE_INITMEM);
}
--
2.31.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v2 3/3] powerpc: Remove init_mem_is_free
@ 2021-09-25 8:31 ` Christophe Leroy
0 siblings, 0 replies; 6+ messages in thread
From: Christophe Leroy @ 2021-09-25 8:31 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: Michael Neuling, linuxppc-dev, linux-kernel
init_mem_is_free is not used anymore. Remove it.
Cc: Michael Neuling <mikey@neuling.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/include/asm/setup.h | 1 -
arch/powerpc/mm/mem.c | 2 --
2 files changed, 3 deletions(-)
diff --git a/arch/powerpc/include/asm/setup.h b/arch/powerpc/include/asm/setup.h
index 6c1a7d217d1a..426a2d8d028f 100644
--- a/arch/powerpc/include/asm/setup.h
+++ b/arch/powerpc/include/asm/setup.h
@@ -9,7 +9,6 @@ extern void ppc_printk_progress(char *s, unsigned short hex);
extern unsigned int rtas_data;
extern unsigned long long memory_limit;
-extern bool init_mem_is_free;
extern void *zalloc_maybe_bootmem(size_t size, gfp_t mask);
struct device_node;
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index c3c4e31462ec..5b1eae6c0356 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -26,7 +26,6 @@
#include <mm/mmu_decl.h>
unsigned long long memory_limit;
-bool init_mem_is_free;
unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
EXPORT_SYMBOL(empty_zero_page);
@@ -312,7 +311,6 @@ void free_initmem(void)
{
ppc_md.progress = ppc_printk_progress;
mark_initmem_nx();
- init_mem_is_free = true;
free_initmem_default(POISON_FREE_INITMEM);
}
--
2.31.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
end of thread, other threads:[~2021-09-25 12:26 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
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2021-09-25 8:31 [PATCH v2 1/3] powerpc/code-patching: Improve verification of patchability Christophe Leroy
2021-09-25 8:31 ` Christophe Leroy
2021-09-25 8:31 ` [PATCH v2 2/3] powerpc: Stop using init_mem_is_free Christophe Leroy
2021-09-25 8:31 ` Christophe Leroy
2021-09-25 8:31 ` [PATCH v2 3/3] powerpc: Remove init_mem_is_free Christophe Leroy
2021-09-25 8:31 ` Christophe Leroy
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