From: Nadav Amit <[email protected]>
There are inconsistencies and some issues in marking functions as
notrace. On one hand, all inline functions are marked as "notrace" and
some libraries cannot be traced. As more users and tools try to make use
of the tracing functionality, it is beneficial to allow their tracing as
possible.
At the same time, some functions should not be traced but are not marked
as notrace.
These patch address issues that I encountered during work on an
automatic tracing tool.
---
v1->v2:
* Add find_bit to tracable libraries
* Improve the change log to explain the reasons for inline->notrace
* Switch the order of patch 2 and patch 3
Nadav Amit (3):
kprobes: Mark descendents of core_kernel_text as notrace
compiler: inline does not imply notrace
lib: Allow traceing of usercopy, xarray, iov_iter, find_bit
arch/arm/kernel/process.c | 2 +-
arch/ia64/mm/init.c | 2 +-
arch/x86/entry/vsyscall/vsyscall_64.c | 2 +-
arch/x86/um/mem_32.c | 2 +-
include/asm-generic/sections.h | 6 +++---
include/linux/compiler_types.h | 2 +-
include/linux/kallsyms.h | 6 +++---
include/linux/mm.h | 2 +-
lib/Makefile | 5 +++++
9 files changed, 17 insertions(+), 12 deletions(-)
--
2.25.1
From: Nadav Amit <[email protected]>
Commit c0d80ddab899 ("kernel/extable.c: mark core_kernel_text notrace")
disabled the tracing of core_kernel_text to avoid recursive calls. For
the same reasons, all the functions in the dynamic extents of
core_kernel_text should be marked as notrace.
Cc: Marcin Nowakowski <[email protected]>
Signed-off-by: Nadav Amit <[email protected]>
---
arch/arm/kernel/process.c | 2 +-
arch/ia64/mm/init.c | 2 +-
arch/x86/entry/vsyscall/vsyscall_64.c | 2 +-
arch/x86/um/mem_32.c | 2 +-
include/asm-generic/sections.h | 6 +++---
include/linux/kallsyms.h | 6 +++---
include/linux/mm.h | 2 +-
7 files changed, 11 insertions(+), 11 deletions(-)
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
index 0e8ff85890ad..a8c0d0a06664 100644
--- a/arch/arm/kernel/process.c
+++ b/arch/arm/kernel/process.c
@@ -330,7 +330,7 @@ int in_gate_area(struct mm_struct *mm, unsigned long addr)
return (addr >= gate_vma.vm_start) && (addr < gate_vma.vm_end);
}
-int in_gate_area_no_mm(unsigned long addr)
+notrace int in_gate_area_no_mm(unsigned long addr)
{
return in_gate_area(NULL, addr);
}
diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c
index 7f5353e28516..6dbd3acbe837 100644
--- a/arch/ia64/mm/init.c
+++ b/arch/ia64/mm/init.c
@@ -284,7 +284,7 @@ struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
return &gate_vma;
}
-int in_gate_area_no_mm(unsigned long addr)
+notrace int in_gate_area_no_mm(unsigned long addr)
{
if ((addr >= FIXADDR_USER_START) && (addr < FIXADDR_USER_END))
return 1;
diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c
index e0ca8120aea8..2d1d09877f0c 100644
--- a/arch/x86/entry/vsyscall/vsyscall_64.c
+++ b/arch/x86/entry/vsyscall/vsyscall_64.c
@@ -340,7 +340,7 @@ int in_gate_area(struct mm_struct *mm, unsigned long addr)
* context. It is less reliable than using a task's mm and may give
* false positives.
*/
-int in_gate_area_no_mm(unsigned long addr)
+notrace int in_gate_area_no_mm(unsigned long addr)
{
return vsyscall_mode != NONE && (addr & PAGE_MASK) == VSYSCALL_ADDR;
}
diff --git a/arch/x86/um/mem_32.c b/arch/x86/um/mem_32.c
index 29b2203bc82c..1f92840af2f3 100644
--- a/arch/x86/um/mem_32.c
+++ b/arch/x86/um/mem_32.c
@@ -28,7 +28,7 @@ struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
return FIXADDR_USER_START ? &gate_vma : NULL;
}
-int in_gate_area_no_mm(unsigned long addr)
+notrace int in_gate_area_no_mm(unsigned long addr)
{
if (!FIXADDR_USER_START)
return 0;
diff --git a/include/asm-generic/sections.h b/include/asm-generic/sections.h
index db13bb620f52..d519965b67bf 100644
--- a/include/asm-generic/sections.h
+++ b/include/asm-generic/sections.h
@@ -188,7 +188,7 @@ static inline bool is_kernel_rodata(unsigned long addr)
*
* Returns: true if the address is located in .init.text, false otherwise.
*/
-static inline bool is_kernel_inittext(unsigned long addr)
+static notrace inline bool is_kernel_inittext(unsigned long addr)
{
return addr >= (unsigned long)_sinittext &&
addr < (unsigned long)_einittext;
@@ -203,7 +203,7 @@ static inline bool is_kernel_inittext(unsigned long addr)
* Returns: true if the address is located in .text, false otherwise.
* Note: an internal helper, only check the range of _stext to _etext.
*/
-static inline bool __is_kernel_text(unsigned long addr)
+static notrace inline bool __is_kernel_text(unsigned long addr)
{
return addr >= (unsigned long)_stext &&
addr < (unsigned long)_etext;
@@ -219,7 +219,7 @@ static inline bool __is_kernel_text(unsigned long addr)
* and range from __init_begin to __init_end, which can be outside
* of the _stext to _end range.
*/
-static inline bool __is_kernel(unsigned long addr)
+static notrace inline bool __is_kernel(unsigned long addr)
{
return ((addr >= (unsigned long)_stext &&
addr < (unsigned long)_end) ||
diff --git a/include/linux/kallsyms.h b/include/linux/kallsyms.h
index fe3c9993b5bf..e11743e68124 100644
--- a/include/linux/kallsyms.h
+++ b/include/linux/kallsyms.h
@@ -24,21 +24,21 @@
struct cred;
struct module;
-static inline int is_kernel_text(unsigned long addr)
+static notrace inline int is_kernel_text(unsigned long addr)
{
if (__is_kernel_text(addr))
return 1;
return in_gate_area_no_mm(addr);
}
-static inline int is_kernel(unsigned long addr)
+static notrace inline int is_kernel(unsigned long addr)
{
if (__is_kernel(addr))
return 1;
return in_gate_area_no_mm(addr);
}
-static inline int is_ksym_addr(unsigned long addr)
+static notrace inline int is_ksym_addr(unsigned long addr)
{
if (IS_ENABLED(CONFIG_KALLSYMS_ALL))
return is_kernel(addr);
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 27ce77080c79..e71ea764659c 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -3485,7 +3485,7 @@ static inline struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
{
return NULL;
}
-static inline int in_gate_area_no_mm(unsigned long addr) { return 0; }
+static notrace inline int in_gate_area_no_mm(unsigned long addr) { return 0; }
static inline int in_gate_area(struct mm_struct *mm, unsigned long addr)
{
return 0;
--
2.25.1