| Message ID | 20211110003717.1150965-4-jniethe5@gmail.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | Use per-CPU temporary mappings for patching on Radix MMU | expand |
Hi Jordan Le 10/11/2021 à 01:37, Jordan Niethe a écrit : > From: "Christopher M. Riedl" <cmr@bluescreens.de> > > Rework code-patching with STRICT_KERNEL_RWX to prepare for a later patch > which uses a temporary mm for patching under the Book3s64 Radix MMU. > Make improvements by adding a WARN_ON when the patchsite doesn't match > after patching and return the error from __patch_instruction() properly. > > Signed-off-by: Christopher M. Riedl <cmr@bluescreens.de> > Signed-off-by: Jordan Niethe <jniethe5@gmail.com> > --- > v7: still pass addr to map_patch_area() This patch doesn-t apply, can you rebase the series ? Thanks Christophe > --- > arch/powerpc/lib/code-patching.c | 20 ++++++++++---------- > 1 file changed, 10 insertions(+), 10 deletions(-) > > diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c > index 29a30c3068ff..d586bf9c7581 100644 > --- a/arch/powerpc/lib/code-patching.c > +++ b/arch/powerpc/lib/code-patching.c > @@ -75,6 +75,7 @@ static inline void stop_using_temp_mm(struct temp_mm_state prev_state) > } > > static DEFINE_PER_CPU(struct vm_struct *, text_poke_area); > +static DEFINE_PER_CPU(unsigned long, cpu_patching_addr); > > static int text_area_cpu_up(unsigned int cpu) > { > @@ -87,6 +88,7 @@ static int text_area_cpu_up(unsigned int cpu) > return -1; > } > this_cpu_write(text_poke_area, area); > + this_cpu_write(cpu_patching_addr, (unsigned long)area->addr); > > return 0; > } > @@ -172,11 +174,10 @@ static inline int unmap_patch_area(unsigned long addr) > > static int do_patch_instruction(u32 *addr, struct ppc_inst instr) > { > - int err; > + int err, rc = 0; > u32 *patch_addr = NULL; > unsigned long flags; > unsigned long text_poke_addr; > - unsigned long kaddr = (unsigned long)addr; > > /* > * During early early boot patch_instruction is called > @@ -188,15 +189,13 @@ static int do_patch_instruction(u32 *addr, struct ppc_inst instr) > > local_irq_save(flags); > > - text_poke_addr = (unsigned long)__this_cpu_read(text_poke_area)->addr; > - if (map_patch_area(addr, text_poke_addr)) { > - err = -1; > + text_poke_addr = __this_cpu_read(cpu_patching_addr); > + err = map_patch_area(addr, text_poke_addr); > + if (err) > goto out; > - } > - > - patch_addr = (u32 *)(text_poke_addr + (kaddr & ~PAGE_MASK)); > > - __patch_instruction(addr, instr, patch_addr); > + patch_addr = (u32 *)(text_poke_addr | offset_in_page(addr)); > + rc = __patch_instruction(addr, instr, patch_addr); > > err = unmap_patch_area(text_poke_addr); > if (err) > @@ -204,8 +203,9 @@ static int do_patch_instruction(u32 *addr, struct ppc_inst instr) > > out: > local_irq_restore(flags); > + WARN_ON(!ppc_inst_equal(ppc_inst_read(addr), instr)); > > - return err; > + return rc ? rc : err; > } > #else /* !CONFIG_STRICT_KERNEL_RWX */ >
On Sat, Mar 12, 2022 at 6:30 PM Christophe Leroy <christophe.leroy@csgroup.eu> wrote: > > Hi Jordan > > Le 10/11/2021 à 01:37, Jordan Niethe a écrit : > > From: "Christopher M. Riedl" <cmr@bluescreens.de> > > > > Rework code-patching with STRICT_KERNEL_RWX to prepare for a later patch > > which uses a temporary mm for patching under the Book3s64 Radix MMU. > > Make improvements by adding a WARN_ON when the patchsite doesn't match > > after patching and return the error from __patch_instruction() properly. > > > > Signed-off-by: Christopher M. Riedl <cmr@bluescreens.de> > > Signed-off-by: Jordan Niethe <jniethe5@gmail.com> > > --- > > v7: still pass addr to map_patch_area() > > > This patch doesn-t apply, can you rebase the series ? Yep, will do. > > Thanks > Christophe > > > --- > > arch/powerpc/lib/code-patching.c | 20 ++++++++++---------- > > 1 file changed, 10 insertions(+), 10 deletions(-) > > > > diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c > > index 29a30c3068ff..d586bf9c7581 100644 > > --- a/arch/powerpc/lib/code-patching.c > > +++ b/arch/powerpc/lib/code-patching.c > > @@ -75,6 +75,7 @@ static inline void stop_using_temp_mm(struct temp_mm_state prev_state) > > } > > > > static DEFINE_PER_CPU(struct vm_struct *, text_poke_area); > > +static DEFINE_PER_CPU(unsigned long, cpu_patching_addr); > > > > static int text_area_cpu_up(unsigned int cpu) > > { > > @@ -87,6 +88,7 @@ static int text_area_cpu_up(unsigned int cpu) > > return -1; > > } > > this_cpu_write(text_poke_area, area); > > + this_cpu_write(cpu_patching_addr, (unsigned long)area->addr); > > > > return 0; > > } > > @@ -172,11 +174,10 @@ static inline int unmap_patch_area(unsigned long addr) > > > > static int do_patch_instruction(u32 *addr, struct ppc_inst instr) > > { > > - int err; > > + int err, rc = 0; > > u32 *patch_addr = NULL; > > unsigned long flags; > > unsigned long text_poke_addr; > > - unsigned long kaddr = (unsigned long)addr; > > > > /* > > * During early early boot patch_instruction is called > > @@ -188,15 +189,13 @@ static int do_patch_instruction(u32 *addr, struct ppc_inst instr) > > > > local_irq_save(flags); > > > > - text_poke_addr = (unsigned long)__this_cpu_read(text_poke_area)->addr; > > - if (map_patch_area(addr, text_poke_addr)) { > > - err = -1; > > + text_poke_addr = __this_cpu_read(cpu_patching_addr); > > + err = map_patch_area(addr, text_poke_addr); > > + if (err) > > goto out; > > - } > > - > > - patch_addr = (u32 *)(text_poke_addr + (kaddr & ~PAGE_MASK)); > > > > - __patch_instruction(addr, instr, patch_addr); > > + patch_addr = (u32 *)(text_poke_addr | offset_in_page(addr)); > > + rc = __patch_instruction(addr, instr, patch_addr); > > > > err = unmap_patch_area(text_poke_addr); > > if (err) > > @@ -204,8 +203,9 @@ static int do_patch_instruction(u32 *addr, struct ppc_inst instr) > > > > out: > > local_irq_restore(flags); > > + WARN_ON(!ppc_inst_equal(ppc_inst_read(addr), instr)); > > > > - return err; > > + return rc ? rc : err; > > } > > #else /* !CONFIG_STRICT_KERNEL_RWX */ > >
diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c index 29a30c3068ff..d586bf9c7581 100644 --- a/arch/powerpc/lib/code-patching.c +++ b/arch/powerpc/lib/code-patching.c @@ -75,6 +75,7 @@ static inline void stop_using_temp_mm(struct temp_mm_state prev_state) } static DEFINE_PER_CPU(struct vm_struct *, text_poke_area); +static DEFINE_PER_CPU(unsigned long, cpu_patching_addr); static int text_area_cpu_up(unsigned int cpu) { @@ -87,6 +88,7 @@ static int text_area_cpu_up(unsigned int cpu) return -1; } this_cpu_write(text_poke_area, area); + this_cpu_write(cpu_patching_addr, (unsigned long)area->addr); return 0; } @@ -172,11 +174,10 @@ static inline int unmap_patch_area(unsigned long addr) static int do_patch_instruction(u32 *addr, struct ppc_inst instr) { - int err; + int err, rc = 0; u32 *patch_addr = NULL; unsigned long flags; unsigned long text_poke_addr; - unsigned long kaddr = (unsigned long)addr; /* * During early early boot patch_instruction is called @@ -188,15 +189,13 @@ static int do_patch_instruction(u32 *addr, struct ppc_inst instr) local_irq_save(flags); - text_poke_addr = (unsigned long)__this_cpu_read(text_poke_area)->addr; - if (map_patch_area(addr, text_poke_addr)) { - err = -1; + text_poke_addr = __this_cpu_read(cpu_patching_addr); + err = map_patch_area(addr, text_poke_addr); + if (err) goto out; - } - - patch_addr = (u32 *)(text_poke_addr + (kaddr & ~PAGE_MASK)); - __patch_instruction(addr, instr, patch_addr); + patch_addr = (u32 *)(text_poke_addr | offset_in_page(addr)); + rc = __patch_instruction(addr, instr, patch_addr); err = unmap_patch_area(text_poke_addr); if (err) @@ -204,8 +203,9 @@ static int do_patch_instruction(u32 *addr, struct ppc_inst instr) out: local_irq_restore(flags); + WARN_ON(!ppc_inst_equal(ppc_inst_read(addr), instr)); - return err; + return rc ? rc : err; } #else /* !CONFIG_STRICT_KERNEL_RWX */