search for: ftrace_modify_code_direct

...+#endif + #endif /* _ASM_X86_SECTIONS_H */ diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index 01ebcb6f263e..73b3c30cb7a3 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -102,7 +102,7 @@ static const unsigned char *ftrace_nop_replace(void) static int ftrace_modify_code_direct(unsigned long ip, unsigned const char *old_code, - unsigned const char *new_code) + unsigned const char *new_code) { unsigned char replaced[MCOUNT_INSN_SIZE]; @@ -135,6 +135,44 @@ ftrace_modify_code_direct(unsigned long ip, unsigned const char *old_code, return 0; } +/* Bytes befo...

...+#endif + #endif /* _ASM_X86_SECTIONS_H */ diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index 01ebcb6f263e..21bde498f1a9 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -102,7 +102,7 @@ static const unsigned char *ftrace_nop_replace(void) static int ftrace_modify_code_direct(unsigned long ip, unsigned const char *old_code, - unsigned const char *new_code) + unsigned const char *new_code) { unsigned char replaced[MCOUNT_INSN_SIZE]; @@ -135,6 +135,44 @@ ftrace_modify_code_direct(unsigned long ip, unsigned const char *old_code, return 0; } +/* Bytes befo...

...dules that are _not_ compiled with PIE, see below. > return addr; > } > > diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c > index 01ebcb6f263e..73b3c30cb7a3 100644 > --- a/arch/x86/kernel/ftrace.c > +++ b/arch/x86/kernel/ftrace.c > @@ -135,6 +135,44 @@ ftrace_modify_code_direct(unsigned long ip, unsigned const char *old_code, > return 0; > } > > +/* Bytes before call GOT offset */ > +const unsigned char got_call_preinsn[] = { 0xff, 0x15 }; > + > +static int > +ftrace_modify_initial_code(unsigned long ip, unsigned const char *old_code, > +...

...dules that are _not_ compiled with PIE, see below. > return addr; > } > > diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c > index 01ebcb6f263e..73b3c30cb7a3 100644 > --- a/arch/x86/kernel/ftrace.c > +++ b/arch/x86/kernel/ftrace.c > @@ -135,6 +135,44 @@ ftrace_modify_code_direct(unsigned long ip, unsigned const char *old_code, > return 0; > } > > +/* Bytes before call GOT offset */ > +const unsigned char got_call_preinsn[] = { 0xff, 0x15 }; > + > +static int > +ftrace_modify_initial_code(unsigned long ip, unsigned const char *old_code, > +...

...static unsigned long text_ip_addr(unsigned long ip) return ip; } -static const unsigned char *ftrace_nop_replace(void) +static const unsigned char *ftrace_nop_replace(unsigned int size) { - return ideal_nops[NOP_ATOMIC5]; + return ideal_nops[size == 5 ? NOP_ATOMIC5 : size]; } static int -ftrace_modify_code_direct(unsigned long ip, unsigned const char *old_code, - unsigned const char *new_code) +ftrace_modify_code_direct(struct dyn_ftrace *rec, unsigned const char *old_code, + unsigned const char *new_code) { unsigned char replaced[MCOUNT_INSN_SIZE]; + unsigned long ip = rec->ip; + unsigned int...

...dr; > > > } > > > > > > diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c > > > index 01ebcb6f263e..73b3c30cb7a3 100644 > > > --- a/arch/x86/kernel/ftrace.c > > > +++ b/arch/x86/kernel/ftrace.c > > > @@ -135,6 +135,44 @@ ftrace_modify_code_direct(unsigned long ip, unsigned const char *old_code, > > > return 0; > > > } > > > > > > +/* Bytes before call GOT offset */ > > > +const unsigned char got_call_preinsn[] = { 0xff, 0x15 }; > > > + > > > +static int > > > +ftra...

...PIE? > > > return addr; > > } > > > > diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c > > index 01ebcb6f263e..73b3c30cb7a3 100644 > > --- a/arch/x86/kernel/ftrace.c > > +++ b/arch/x86/kernel/ftrace.c > > @@ -135,6 +135,44 @@ ftrace_modify_code_direct(unsigned long ip, unsigned const char *old_code, > > return 0; > > } > > > > +/* Bytes before call GOT offset */ > > +const unsigned char got_call_preinsn[] = { 0xff, 0x15 }; > > + > > +static int > > +ftrace_modify_initial_code(unsigned long ip,...

These patches make the changes necessary to build the kernel as Position Independent Executable (PIE) on x86_64. A PIE kernel can be relocated below the top 2G of the virtual address space. It allows to optionally extend the KASLR randomization range from 1G to 3G. Thanks a lot to Ard Biesheuvel & Kees Cook on their feedback on compiler changes, PIE support and KASLR in general. Thanks to

These patches make the changes necessary to build the kernel as Position Independent Executable (PIE) on x86_64. A PIE kernel can be relocated below the top 2G of the virtual address space. It allows to optionally extend the KASLR randomization range from 1G to 3G. Thanks a lot to Ard Biesheuvel & Kees Cook on their feedback on compiler changes, PIE support and KASLR in general. Thanks to

Changes: - patch v3: - Update on message to describe longer term PIE goal. - Minor change on ftrace if condition. - Changed code using xchgq. - patch v2: - Adapt patch to work post KPTI and compiler changes - Redo all performance testing with latest configs and compilers - Simplify mov macro on PIE (MOVABS now) - Reduce GOT footprint - patch v1: - Simplify ftrace

Changes: - patch v2: - Adapt patch to work post KPTI and compiler changes - Redo all performance testing with latest configs and compilers - Simplify mov macro on PIE (MOVABS now) - Reduce GOT footprint - patch v1: - Simplify ftrace implementation. - Use gcc mstack-protector-guard-reg=%gs with PIE when possible. - rfc v3: - Use --emit-relocs instead of -pie to reduce

Changes: - patch v2: - Adapt patch to work post KPTI and compiler changes - Redo all performance testing with latest configs and compilers - Simplify mov macro on PIE (MOVABS now) - Reduce GOT footprint - patch v1: - Simplify ftrace implementation. - Use gcc mstack-protector-guard-reg=%gs with PIE when possible. - rfc v3: - Use --emit-relocs instead of -pie to reduce

Changes: - patch v1: - Simplify ftrace implementation. - Use gcc mstack-protector-guard-reg=%gs with PIE when possible. - rfc v3: - Use --emit-relocs instead of -pie to reduce dynamic relocation space on mapped memory. It also simplifies the relocation process. - Move the start the module section next to the kernel. Remove the need for -mcmodel=large on modules. Extends

Changes: - patch v1: - Simplify ftrace implementation. - Use gcc mstack-protector-guard-reg=%gs with PIE when possible. - rfc v3: - Use --emit-relocs instead of -pie to reduce dynamic relocation space on mapped memory. It also simplifies the relocation process. - Move the start the module section next to the kernel. Remove the need for -mcmodel=large on modules. Extends