* Re: [PATCH 03/16] debug_vm_pgtable/set_pte: Don't use set_pte_at to update an existing pte entry
From: Anshuman Khandual @ 2020-08-12 9:12 UTC (permalink / raw)
To: Aneesh Kumar K.V, linux-mm, akpm; +Cc: linuxppc-dev
In-Reply-To: <20200812063358.369514-3-aneesh.kumar@linux.ibm.com>
On 08/12/2020 12:03 PM, Aneesh Kumar K.V wrote:
> set_pte_at() should not be used to set a pte entry at locations that
> already holds a valid pte entry. Architectures like ppc64 don't do TLB
> invalidate in set_pte_at() and hence expect it to be used to set locations
> that are not a valid PTE.
Even though set_pte_at() is not really a arch page table helper and
very much arch specific, I just wonder why this deviation on ppc64
as compared to other platforms. Detecting such semantics variation
across platforms is an objective of this test.
As small nit.
Please follow the existing subject format for all patches in here.
It will improve readability and also help understand these changes
better, later on.
mm/debug_vm_pgtable: <Specify changes to an individual test>
>
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
> ---
> mm/debug_vm_pgtable.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
> index 4c32063a8acf..02a7c20aa4a2 100644
> --- a/mm/debug_vm_pgtable.c
> +++ b/mm/debug_vm_pgtable.c
> @@ -81,8 +81,6 @@ static void __init pte_advanced_tests(struct mm_struct *mm,
> pte = ptep_get(ptep);
> WARN_ON(pte_write(pte));
>
> - pte = pfn_pte(pfn, prot);
> - set_pte_at(mm, vaddr, ptep, pte);
> ptep_get_and_clear(mm, vaddr, ptep);
> pte = ptep_get(ptep);
> WARN_ON(!pte_none(pte));
This makes sense. But could you please fold this code stanza with
the previous one in order to imply that 'ptep' did have some valid
entry before being cleared and checked against pte_none().
> @@ -97,12 +95,14 @@ static void __init pte_advanced_tests(struct mm_struct *mm,
> pte = ptep_get(ptep);
> WARN_ON(!(pte_write(pte) && pte_dirty(pte)));
>
> - pte = pfn_pte(pfn, prot);
> - set_pte_at(mm, vaddr, ptep, pte);
> ptep_get_and_clear_full(mm, vaddr, ptep, 1);
> pte = ptep_get(ptep);
> WARN_ON(!pte_none(pte));
Same, please fold back.
>
> + /*
> + * We should clear pte before we do set_pte_at
> + */
> + pte = ptep_get_and_clear(mm, vaddr, ptep);
> pte = pte_mkyoung(pte);
> set_pte_at(mm, vaddr, ptep, pte);
> ptep_test_and_clear_young(vma, vaddr, ptep);
>
The comment above should also explain details that are mentioned
in the commit message i.e how platforms such as ppc64 expects a
clear pte entry for set_pte_at() to work.
^ permalink raw reply
* Re: [PATCH 03/16] debug_vm_pgtable/set_pte: Don't use set_pte_at to update an existing pte entry
From: Aneesh Kumar K.V @ 2020-08-12 9:22 UTC (permalink / raw)
To: Anshuman Khandual, linux-mm, akpm; +Cc: linuxppc-dev
In-Reply-To: <94ed519a-2cf2-af50-82be-2a559dee7d86@arm.com>
On 8/12/20 2:42 PM, Anshuman Khandual wrote:
>
>
> On 08/12/2020 12:03 PM, Aneesh Kumar K.V wrote:
>> set_pte_at() should not be used to set a pte entry at locations that
>> already holds a valid pte entry. Architectures like ppc64 don't do TLB
>> invalidate in set_pte_at() and hence expect it to be used to set locations
>> that are not a valid PTE.
>
> Even though set_pte_at() is not really a arch page table helper and
> very much arch specific, I just wonder why this deviation on ppc64
> as compared to other platforms. Detecting such semantics variation
> across platforms is an objective of this test.
Not sure what you mean by set_pte_at is not a page table helper. Generic
kernel use that helper to set a pte entry.
Now w.r.t ppc64 behavior this was discussed multiple times. I guess
Linux kernel always used set_pte_at on a none pte entry. We had some
exceptions in the recent past. But all fixed when noticed.
383321ab8578dfe3bbcc0bc5604c0f8ae08a5c98
mm/hugetlb/migration: use set_huge_pte_at instead of set_pte_at
cee216a696b2004017a5ecb583366093d90b1568
mm/autonuma: don't use set_pte_at when updating protnone ptes
56eecdb912b536a4fa97fb5bfe5a940a54d79be6
mm: Use ptep/pmdp_set_numa() for updating _PAGE_NUMA bit
Yes. Having a testcase like this help
>
> As small nit.
>
> Please follow the existing subject format for all patches in here.
> It will improve readability and also help understand these changes
> better, later on.
>
> mm/debug_vm_pgtable: <Specify changes to an individual test>
>
>>
>> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
>> ---
>> mm/debug_vm_pgtable.c | 8 ++++----
>> 1 file changed, 4 insertions(+), 4 deletions(-)
>>
>> diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
>> index 4c32063a8acf..02a7c20aa4a2 100644
>> --- a/mm/debug_vm_pgtable.c
>> +++ b/mm/debug_vm_pgtable.c
>> @@ -81,8 +81,6 @@ static void __init pte_advanced_tests(struct mm_struct *mm,
>> pte = ptep_get(ptep);
>> WARN_ON(pte_write(pte));
>>
>> - pte = pfn_pte(pfn, prot);
>> - set_pte_at(mm, vaddr, ptep, pte);
>> ptep_get_and_clear(mm, vaddr, ptep);
>> pte = ptep_get(ptep);
>> WARN_ON(!pte_none(pte));
>
> This makes sense. But could you please fold this code stanza with
> the previous one in order to imply that 'ptep' did have some valid
> entry before being cleared and checked against pte_none().
>
will do that
>> @@ -97,12 +95,14 @@ static void __init pte_advanced_tests(struct mm_struct *mm,
>> pte = ptep_get(ptep);
>> WARN_ON(!(pte_write(pte) && pte_dirty(pte)));
>>
>> - pte = pfn_pte(pfn, prot);
>> - set_pte_at(mm, vaddr, ptep, pte);
>> ptep_get_and_clear_full(mm, vaddr, ptep, 1);
>> pte = ptep_get(ptep);
>> WARN_ON(!pte_none(pte));
>
> Same, please fold back.
>
ok
>> + /*
>> + * We should clear pte before we do set_pte_at
>> + */
>> + pte = ptep_get_and_clear(mm, vaddr, ptep);
>> pte = pte_mkyoung(pte);
>> set_pte_at(mm, vaddr, ptep, pte);
>> ptep_test_and_clear_young(vma, vaddr, ptep);
>>
>
> The comment above should also explain details that are mentioned
> in the commit message i.e how platforms such as ppc64 expects a
> clear pte entry for set_pte_at() to work.
>
I don't think it is specific to ppc64. There is nothing specific to
ppc64 architecture in there. It is an optimization used in kernel to
help architecture avoid TLB flush. I will update the comment as below
/* We should clear pte before we do set_pte_at so that set_pte_at don't
find a valid pte at ptep *?
is that good?
-aneesh
^ permalink raw reply
* Re: [PATCH 04/16] debug_vm_pgtables/hugevmap: Use the arch helper to identify huge vmap support.
From: Anshuman Khandual @ 2020-08-12 10:30 UTC (permalink / raw)
To: Aneesh Kumar K.V, linux-mm, akpm; +Cc: linuxppc-dev
In-Reply-To: <20200812063358.369514-4-aneesh.kumar@linux.ibm.com>
On 08/12/2020 12:03 PM, Aneesh Kumar K.V wrote:
> ppc64 supports huge vmap only with radix translation. Hence use arch helper
> to determine the huge vmap support.
>
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
> ---
> mm/debug_vm_pgtable.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
> index 02a7c20aa4a2..679bb3d289a3 100644
> --- a/mm/debug_vm_pgtable.c
> +++ b/mm/debug_vm_pgtable.c
> @@ -206,7 +206,7 @@ static void __init pmd_huge_tests(pmd_t *pmdp, unsigned long pfn, pgprot_t prot)
> {
> pmd_t pmd;
>
> - if (!IS_ENABLED(CONFIG_HAVE_ARCH_HUGE_VMAP))
> + if (!arch_ioremap_pmd_supported())
> return;
>
> pr_debug("Validating PMD huge\n");
>
Problem is arch_ioremap_pmd_supported() symbol which should also be
explicitly included via <linux/io.h>, is not available without the
config CONFIG_HAVE_ARCH_HUGE_VMAP. ioremap_pmd_enabled() should have
been better here and has a fallback for !CONFIG_HAVE_ARCH_HUGE_VMAP.
But then the symbol is local to that file. Unless we would like to
make ioremap_pxx_enabled generally available, the remaining option
would be to wrap pxx_huge_tests() with CONFIG_HAVE_ARCH_HUGE_VMAP.
Similar changes should also be done for pud_huge_tests() as well.
^ permalink raw reply
* Re: [PATCH 1/2] lockdep: improve current->(hard|soft)irqs_enabled synchronisation with actual irq state
From: peterz @ 2020-08-12 10:35 UTC (permalink / raw)
To: Nicholas Piggin
Cc: linux-arch, Alexey Kardashevskiy, Will Deacon, linux-kernel,
Ingo Molnar, linuxppc-dev
In-Reply-To: <1597220073.mbvcty6ghk.astroid@bobo.none>
On Wed, Aug 12, 2020 at 06:18:28PM +1000, Nicholas Piggin wrote:
> Excerpts from peterz@infradead.org's message of August 7, 2020 9:11 pm:
> >
> > What's wrong with something like this?
> >
> > AFAICT there's no reason to actually try and add IRQ tracing here, it's
> > just a hand full of instructions at the most.
>
> Because we may want to use that in other places as well, so it would
> be nice to have tracing.
>
> Hmm... also, I thought NMI context was free to call local_irq_save/restore
> anyway so the bug would still be there in those cases?
NMI code has in_nmi() true, in which case the IRQ tracing is disabled
(except for x86 which has CONFIG_TRACE_IRQFLAGS_NMI).
^ permalink raw reply
* Re: [PATCH 05/16] debug_vm_pgtable/savedwrite: Enable savedwrite test with CONFIG_NUMA_BALANCING
From: Anshuman Khandual @ 2020-08-12 11:24 UTC (permalink / raw)
To: Aneesh Kumar K.V, linux-mm, akpm; +Cc: linuxppc-dev
In-Reply-To: <20200812063358.369514-5-aneesh.kumar@linux.ibm.com>
On 08/12/2020 12:03 PM, Aneesh Kumar K.V wrote:
> Saved write support was added to track the write bit of a pte after marking the
> pte protnone. This was done so that AUTONUMA can convert a write pte to protnone
> and still track the old write bit. When converting it back we set the pte write
> bit correctly thereby avoiding a write fault again. Hence enable the test only
> when CONFIG_NUMA_BALANCING is enabled.
This has not been a problem on architectures that do not define pxx_savedwrite()
as they fallback on standard pxx_write() helpers. But ppc64 defines a fall back
for pte_savedwrite() when !CONFIG_NUMA_BALANCING, which always returns false.
Agreed, it makes sense to add CONFIG_NUMA_BALANCING check. But a simple runtime
check will do as the functions are always visible/defined.
if (!IS_ENABLED(CONFIG_NUMA_BALANCING))
return;
>
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
> ---
> mm/debug_vm_pgtable.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
> index 679bb3d289a3..de8a62d0a931 100644
> --- a/mm/debug_vm_pgtable.c
> +++ b/mm/debug_vm_pgtable.c
> @@ -110,6 +110,7 @@ static void __init pte_advanced_tests(struct mm_struct *mm,
> WARN_ON(pte_young(pte));
> }
>
> +#ifdef CONFIG_NUMA_BALANCING
> static void __init pte_savedwrite_tests(unsigned long pfn, pgprot_t prot)
> {
> pte_t pte = pfn_pte(pfn, prot);
> @@ -118,6 +119,8 @@ static void __init pte_savedwrite_tests(unsigned long pfn, pgprot_t prot)
> WARN_ON(!pte_savedwrite(pte_mk_savedwrite(pte_clear_savedwrite(pte))));
> WARN_ON(pte_savedwrite(pte_clear_savedwrite(pte_mk_savedwrite(pte))));
> }
> +#endif
> +
> #ifdef CONFIG_TRANSPARENT_HUGEPAGE
> static void __init pmd_basic_tests(unsigned long pfn, pgprot_t prot)
> {
> @@ -221,6 +224,7 @@ static void __init pmd_huge_tests(pmd_t *pmdp, unsigned long pfn, pgprot_t prot)
> WARN_ON(!pmd_none(pmd));
> }
>
> +#ifdef CONFIG_NUMA_BALANCING
> static void __init pmd_savedwrite_tests(unsigned long pfn, pgprot_t prot)
> {
> pmd_t pmd = pfn_pmd(pfn, prot);
> @@ -229,6 +233,7 @@ static void __init pmd_savedwrite_tests(unsigned long pfn, pgprot_t prot)
> WARN_ON(!pmd_savedwrite(pmd_mk_savedwrite(pmd_clear_savedwrite(pmd))));
> WARN_ON(pmd_savedwrite(pmd_clear_savedwrite(pmd_mk_savedwrite(pmd))));
> }
> +#endif
>
> #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
> static void __init pud_basic_tests(unsigned long pfn, pgprot_t prot)
> @@ -1005,8 +1010,10 @@ static int __init debug_vm_pgtable(void)
> pmd_huge_tests(pmdp, pmd_aligned, prot);
> pud_huge_tests(pudp, pud_aligned, prot);
>
> +#ifdef CONFIG_NUMA_BALANCING
> pte_savedwrite_tests(pte_aligned, prot);
> pmd_savedwrite_tests(pmd_aligned, prot);
> +#endif
BTW, config wrappers should be avoided at the call site. If and when needed
a stub is defined for !CONFIG_XXX_XXX.
>
> pte_unmap_unlock(ptep, ptl);
>
>
^ permalink raw reply
* Re: [PATCH 07/16] debug_vm_pgtable/THP: Mark the pte entry huge before using set_pud_at
From: Anshuman Khandual @ 2020-08-12 11:49 UTC (permalink / raw)
To: Aneesh Kumar K.V, linux-mm, akpm; +Cc: linuxppc-dev
In-Reply-To: <20200812063358.369514-7-aneesh.kumar@linux.ibm.com>
On 08/12/2020 12:03 PM, Aneesh Kumar K.V wrote:
> kernel expect entries to be marked huge before we use set_pud_at().
>
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
> ---
> mm/debug_vm_pgtable.c | 11 +++++++----
> 1 file changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
> index b6aca2526e01..cd609a212dd4 100644
> --- a/mm/debug_vm_pgtable.c
> +++ b/mm/debug_vm_pgtable.c
> @@ -265,7 +265,7 @@ static void __init pud_advanced_tests(struct mm_struct *mm,
> unsigned long pfn, unsigned long vaddr,
> pgprot_t prot)
> {
> - pud_t pud = pfn_pud(pfn, prot);
> + pud_t pud;
>
> if (!has_transparent_hugepage())
> return;
> @@ -274,25 +274,28 @@ static void __init pud_advanced_tests(struct mm_struct *mm,
> /* Align the address wrt HPAGE_PUD_SIZE */
> vaddr = (vaddr & HPAGE_PUD_MASK) + HPAGE_PUD_SIZE;
>
> + pud = pud_mkhuge(pfn_pud(pfn, prot));
> set_pud_at(mm, vaddr, pudp, pud);
> pudp_set_wrprotect(mm, vaddr, pudp);
> pud = READ_ONCE(*pudp);
> WARN_ON(pud_write(pud));
>
> #ifndef __PAGETABLE_PMD_FOLDED
> - pud = pfn_pud(pfn, prot);
> +
> + pud = pud_mkhuge(pfn_pud(pfn, prot));
> set_pud_at(mm, vaddr, pudp, pud);
> pudp_huge_get_and_clear(mm, vaddr, pudp);
> pud = READ_ONCE(*pudp);
> WARN_ON(!pud_none(pud));
>
> - pud = pfn_pud(pfn, prot);
> + pud = pud_mkhuge(pfn_pud(pfn, prot));
> set_pud_at(mm, vaddr, pudp, pud);
> pudp_huge_get_and_clear_full(mm, vaddr, pudp, 1);
> pud = READ_ONCE(*pudp);
> WARN_ON(!pud_none(pud));
> #endif /* __PAGETABLE_PMD_FOLDED */
> - pud = pfn_pud(pfn, prot);
> +
> + pud = pud_mkhuge(pfn_pud(pfn, prot));
> pud = pud_wrprotect(pud);
> pud = pud_mkclean(pud);
> set_pud_at(mm, vaddr, pudp, pud);
>
Looks very similar to the previous patch, hence please fold it back.
Seems fair enough that pxx_set_at() expects given entry to be huge.
But would need to run them across enabled platforms to be sure.
^ permalink raw reply
* [RFC PATCH v1 03/19] powerpc/ptrace: Consolidate reg index calculation
From: Christophe Leroy @ 2020-08-12 12:05 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, ldv,
viro
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597233555.git.christophe.leroy@csgroup.eu>
Today we have:
#ifdef CONFIG_PPC32
index = addr >> 2;
if ((addr & 3) || child->thread.regs == NULL)
#else
index = addr >> 3;
if ((addr & 7))
#endif
sizeof(long) has value 4 for PPC32 and value 8 for PPC64.
Dividing by 4 is equivalent to >> 2 and dividing by 8 is equivalent
to >> 3.
And 3 and 7 are respectively (sizeof(long) - 1).
Use sizeof(long) to get rid of the #ifdef CONFIG_PPC32 and consolidate
the calculation and checking.
thread.regs have to be not NULL on both PPC32 and PPC64 so adding
that test on PPC64 is harmless.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/ptrace/ptrace.c | 20 ++++----------------
1 file changed, 4 insertions(+), 16 deletions(-)
diff --git a/arch/powerpc/kernel/ptrace/ptrace.c b/arch/powerpc/kernel/ptrace/ptrace.c
index f6e51be47c6e..0b4645a7a1b4 100644
--- a/arch/powerpc/kernel/ptrace/ptrace.c
+++ b/arch/powerpc/kernel/ptrace/ptrace.c
@@ -55,14 +55,8 @@ long arch_ptrace(struct task_struct *child, long request,
ret = -EIO;
/* convert to index and check */
-#ifdef CONFIG_PPC32
- index = addr >> 2;
- if ((addr & 3) || (index > PT_FPSCR)
- || (child->thread.regs == NULL))
-#else
- index = addr >> 3;
- if ((addr & 7) || (index > PT_FPSCR))
-#endif
+ index = addr / sizeof(long);
+ if ((addr & (sizeof(long) - 1)) || (index > PT_FPSCR) || !child->thread.regs)
break;
CHECK_FULL_REGS(child->thread.regs);
@@ -90,14 +84,8 @@ long arch_ptrace(struct task_struct *child, long request,
ret = -EIO;
/* convert to index and check */
-#ifdef CONFIG_PPC32
- index = addr >> 2;
- if ((addr & 3) || (index > PT_FPSCR)
- || (child->thread.regs == NULL))
-#else
- index = addr >> 3;
- if ((addr & 7) || (index > PT_FPSCR))
-#endif
+ index = addr / sizeof(long);
+ if ((addr & (sizeof(long) - 1)) || (index > PT_FPSCR) || !child->thread.regs)
break;
CHECK_FULL_REGS(child->thread.regs);
--
2.25.0
^ permalink raw reply related
* [RFC PATCH v1 04/19] powerpc/ptrace: Create ptrace_get_fpr() and ptrace_put_fpr()
From: Christophe Leroy @ 2020-08-12 12:05 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, ldv,
viro
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597233555.git.christophe.leroy@csgroup.eu>
On the same model as ptrace_get_reg() and ptrace_put_reg(),
create ptrace_get_fpr() and ptrace_put_fpr() to get/set
the floating points registers.
We move the boundary checkings in them.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/ptrace/Makefile | 1 +
arch/powerpc/kernel/ptrace/ptrace-decl.h | 4 +++
arch/powerpc/kernel/ptrace/ptrace-fpu.c | 40 ++++++++++++++++++++++++
arch/powerpc/kernel/ptrace/ptrace.c | 38 +++++++---------------
4 files changed, 56 insertions(+), 27 deletions(-)
create mode 100644 arch/powerpc/kernel/ptrace/ptrace-fpu.c
diff --git a/arch/powerpc/kernel/ptrace/Makefile b/arch/powerpc/kernel/ptrace/Makefile
index c2f2402ebc8c..77abd1a5a508 100644
--- a/arch/powerpc/kernel/ptrace/Makefile
+++ b/arch/powerpc/kernel/ptrace/Makefile
@@ -6,6 +6,7 @@
CFLAGS_ptrace-view.o += -DUTS_MACHINE='"$(UTS_MACHINE)"'
obj-y += ptrace.o ptrace-view.o
+obj-y += ptrace-fpu.o
obj-$(CONFIG_COMPAT) += ptrace32.o
obj-$(CONFIG_VSX) += ptrace-vsx.o
ifneq ($(CONFIG_VSX),y)
diff --git a/arch/powerpc/kernel/ptrace/ptrace-decl.h b/arch/powerpc/kernel/ptrace/ptrace-decl.h
index 2ddc68412fa8..eafe5f0f6289 100644
--- a/arch/powerpc/kernel/ptrace/ptrace-decl.h
+++ b/arch/powerpc/kernel/ptrace/ptrace-decl.h
@@ -164,6 +164,10 @@ int ptrace_put_reg(struct task_struct *task, int regno, unsigned long data);
extern const struct user_regset_view user_ppc_native_view;
+/* ptrace-fpu */
+int ptrace_get_fpr(struct task_struct *child, int index, unsigned long *data);
+int ptrace_put_fpr(struct task_struct *child, int index, unsigned long data);
+
/* ptrace-(no)adv */
void ppc_gethwdinfo(struct ppc_debug_info *dbginfo);
int ptrace_get_debugreg(struct task_struct *child, unsigned long addr,
diff --git a/arch/powerpc/kernel/ptrace/ptrace-fpu.c b/arch/powerpc/kernel/ptrace/ptrace-fpu.c
new file mode 100644
index 000000000000..8301cb52dd99
--- /dev/null
+++ b/arch/powerpc/kernel/ptrace/ptrace-fpu.c
@@ -0,0 +1,40 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <linux/regset.h>
+
+#include <asm/switch_to.h>
+
+#include "ptrace-decl.h"
+
+int ptrace_get_fpr(struct task_struct *child, int index, unsigned long *data)
+{
+ unsigned int fpidx = index - PT_FPR0;
+
+ if (index > PT_FPSCR)
+ return -EIO;
+
+ flush_fp_to_thread(child);
+ if (fpidx < (PT_FPSCR - PT_FPR0))
+ memcpy(data, &child->thread.TS_FPR(fpidx), sizeof(long));
+ else
+ *data = child->thread.fp_state.fpscr;
+
+ return 0;
+}
+
+int ptrace_put_fpr(struct task_struct *child, int index, unsigned long data)
+{
+ unsigned int fpidx = index - PT_FPR0;
+
+ if (index > PT_FPSCR)
+ return -EIO;
+
+ flush_fp_to_thread(child);
+ if (fpidx < (PT_FPSCR - PT_FPR0))
+ memcpy(&child->thread.TS_FPR(fpidx), &data, sizeof(long));
+ else
+ child->thread.fp_state.fpscr = data;
+
+ return 0;
+}
+
diff --git a/arch/powerpc/kernel/ptrace/ptrace.c b/arch/powerpc/kernel/ptrace/ptrace.c
index 0b4645a7a1b4..3d44b73adb83 100644
--- a/arch/powerpc/kernel/ptrace/ptrace.c
+++ b/arch/powerpc/kernel/ptrace/ptrace.c
@@ -56,24 +56,17 @@ long arch_ptrace(struct task_struct *child, long request,
ret = -EIO;
/* convert to index and check */
index = addr / sizeof(long);
- if ((addr & (sizeof(long) - 1)) || (index > PT_FPSCR) || !child->thread.regs)
+ if ((addr & (sizeof(long) - 1)) || !child->thread.regs)
break;
CHECK_FULL_REGS(child->thread.regs);
- if (index < PT_FPR0) {
+ if (index < PT_FPR0)
ret = ptrace_get_reg(child, (int) index, &tmp);
- if (ret)
- break;
- } else {
- unsigned int fpidx = index - PT_FPR0;
-
- flush_fp_to_thread(child);
- if (fpidx < (PT_FPSCR - PT_FPR0))
- memcpy(&tmp, &child->thread.TS_FPR(fpidx),
- sizeof(long));
- else
- tmp = child->thread.fp_state.fpscr;
- }
+ else
+ ret = ptrace_get_fpr(child, index, &tmp);
+
+ if (ret)
+ break;
ret = put_user(tmp, datalp);
break;
}
@@ -85,23 +78,14 @@ long arch_ptrace(struct task_struct *child, long request,
ret = -EIO;
/* convert to index and check */
index = addr / sizeof(long);
- if ((addr & (sizeof(long) - 1)) || (index > PT_FPSCR) || !child->thread.regs)
+ if ((addr & (sizeof(long) - 1)) || !child->thread.regs)
break;
CHECK_FULL_REGS(child->thread.regs);
- if (index < PT_FPR0) {
+ if (index < PT_FPR0)
ret = ptrace_put_reg(child, index, data);
- } else {
- unsigned int fpidx = index - PT_FPR0;
-
- flush_fp_to_thread(child);
- if (fpidx < (PT_FPSCR - PT_FPR0))
- memcpy(&child->thread.TS_FPR(fpidx), &data,
- sizeof(long));
- else
- child->thread.fp_state.fpscr = data;
- ret = 0;
- }
+ else
+ ret = ptrace_put_fpr(child, index, data);
break;
}
--
2.25.0
^ permalink raw reply related
* [RFC PATCH v1 00/19] powerpc: Switch signal 32 to using user_access_begin() and friends
From: Christophe Leroy @ 2020-08-12 12:05 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, ldv,
viro
Cc: linuxppc-dev, linux-kernel
This series replaces copies to users by unsafe_put_user() and friends
with user_write_access_begin() dance in signal32.
The advantages are:
- No KUAP unlock/lock at every copy
- More readable code.
- Better generated code.
Copying Al Viro who did it on x86 and may have suggestions,
and Dmitry V. Levin who introduced put_compat_sigset()
Christophe Leroy (19):
powerpc/signal: Move inline functions in signal.h
powerpc/ptrace: Move declaration of ptrace_get_reg() and
ptrace_set_reg()
powerpc/ptrace: Consolidate reg index calculation
powerpc/ptrace: Create ptrace_get_fpr() and ptrace_put_fpr()
powerpc/signal: Don't manage floating point regs when no FPU
powerpc/32s: Allow deselecting CONFIG_PPC_FPU on mpc832x
powerpc/signal: Move access_ok() out of get_sigframe()
powerpc/signal: Remove get_clean_sp()
powerpc/signal: Call get_tm_stackpointer() from get_sigframe()
powerpc/signal: Refactor bad frame logging
powerpc/signal32: Simplify logging in handle_rt_signal32()
powerpc/signal32: Regroup copies in save_user_regs() and
save_tm_user_regs()
powerpc/signal32: Create 'unsafe' versions of
copy_[ck][fpr/vsx]_to_user()
powerpc/signal32: Switch save_user_regs() and save_tm_user_regs() to
user_access_begin() logic
powerpc/signal32: Switch handle_signal32() to user_access_begin()
logic
powerpc/signal32: Switch handle_rt_signal32() to user_access_begin()
logic
signal: Add unsafe_put_compat_sigset()
powerpc/signal32: Add and use unsafe_put_sigset_t()
powerpc/signal32: Switch swap_context() to user_access_begin() logic
arch/powerpc/Kconfig | 1 +
arch/powerpc/include/asm/processor.h | 16 +-
arch/powerpc/include/asm/ptrace.h | 6 -
arch/powerpc/kernel/asm-offsets.c | 2 +
arch/powerpc/kernel/process.c | 4 +
arch/powerpc/kernel/ptrace/Makefile | 3 +-
arch/powerpc/kernel/ptrace/ptrace-decl.h | 21 ++
arch/powerpc/kernel/ptrace/ptrace-fpu.c | 40 +++
arch/powerpc/kernel/ptrace/ptrace-view.c | 2 +
arch/powerpc/kernel/ptrace/ptrace.c | 54 +---
arch/powerpc/kernel/signal.c | 59 ++--
arch/powerpc/kernel/signal.h | 109 ++++++-
arch/powerpc/kernel/signal_32.c | 386 ++++++++++++-----------
arch/powerpc/kernel/signal_64.c | 19 +-
arch/powerpc/kernel/traps.c | 2 +
arch/powerpc/platforms/Kconfig.cputype | 15 +-
include/linux/compat.h | 32 ++
17 files changed, 462 insertions(+), 309 deletions(-)
create mode 100644 arch/powerpc/kernel/ptrace/ptrace-fpu.c
--
2.25.0
^ permalink raw reply
* [RFC PATCH v1 02/19] powerpc/ptrace: Move declaration of ptrace_get_reg() and ptrace_set_reg()
From: Christophe Leroy @ 2020-08-12 12:05 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, ldv,
viro
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597233555.git.christophe.leroy@csgroup.eu>
ptrace_get_reg() and ptrace_set_reg() are only used internally by
ptrace.
Move them in arch/powerpc/kernel/ptrace/ptrace-decl.h
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/include/asm/ptrace.h | 6 ------
arch/powerpc/kernel/ptrace/ptrace-decl.h | 3 +++
2 files changed, 3 insertions(+), 6 deletions(-)
diff --git a/arch/powerpc/include/asm/ptrace.h b/arch/powerpc/include/asm/ptrace.h
index 155a197c0aa1..3c3cf537c3bf 100644
--- a/arch/powerpc/include/asm/ptrace.h
+++ b/arch/powerpc/include/asm/ptrace.h
@@ -171,12 +171,6 @@ static inline void regs_set_return_value(struct pt_regs *regs, unsigned long rc)
set_thread_flag(TIF_NOERROR); \
} while(0)
-struct task_struct;
-extern int ptrace_get_reg(struct task_struct *task, int regno,
- unsigned long *data);
-extern int ptrace_put_reg(struct task_struct *task, int regno,
- unsigned long data);
-
#define current_pt_regs() \
((struct pt_regs *)((unsigned long)task_stack_page(current) + THREAD_SIZE) - 1)
diff --git a/arch/powerpc/kernel/ptrace/ptrace-decl.h b/arch/powerpc/kernel/ptrace/ptrace-decl.h
index 67447a6197eb..2ddc68412fa8 100644
--- a/arch/powerpc/kernel/ptrace/ptrace-decl.h
+++ b/arch/powerpc/kernel/ptrace/ptrace-decl.h
@@ -159,6 +159,9 @@ int tm_cgpr32_set(struct task_struct *target, const struct user_regset *regset,
/* ptrace-view */
+int ptrace_get_reg(struct task_struct *task, int regno, unsigned long *data);
+int ptrace_put_reg(struct task_struct *task, int regno, unsigned long data);
+
extern const struct user_regset_view user_ppc_native_view;
/* ptrace-(no)adv */
--
2.25.0
^ permalink raw reply related
* [RFC PATCH v1 01/19] powerpc/signal: Move inline functions in signal.h
From: Christophe Leroy @ 2020-08-12 12:05 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, ldv,
viro
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597233555.git.christophe.leroy@csgroup.eu>
To really be inlined, the functions needs to be defined in the
same C file as the caller, or in an included header.
Move functions from signal .c defined inline in signal.h
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Fixes: 3dd4eb83a9c0 ("powerpc: move common register copy functions from signal_32.c to signal.c")
---
arch/powerpc/kernel/signal.c | 30 --------------------------
arch/powerpc/kernel/signal.h | 41 +++++++++++++++++++++++++++++-------
2 files changed, 33 insertions(+), 38 deletions(-)
diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c
index d15a98c758b8..3b56db02b762 100644
--- a/arch/powerpc/kernel/signal.c
+++ b/arch/powerpc/kernel/signal.c
@@ -133,36 +133,6 @@ unsigned long copy_ckvsx_from_user(struct task_struct *task,
return 0;
}
#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
-#else
-inline unsigned long copy_fpr_to_user(void __user *to,
- struct task_struct *task)
-{
- return __copy_to_user(to, task->thread.fp_state.fpr,
- ELF_NFPREG * sizeof(double));
-}
-
-inline unsigned long copy_fpr_from_user(struct task_struct *task,
- void __user *from)
-{
- return __copy_from_user(task->thread.fp_state.fpr, from,
- ELF_NFPREG * sizeof(double));
-}
-
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
-inline unsigned long copy_ckfpr_to_user(void __user *to,
- struct task_struct *task)
-{
- return __copy_to_user(to, task->thread.ckfp_state.fpr,
- ELF_NFPREG * sizeof(double));
-}
-
-inline unsigned long copy_ckfpr_from_user(struct task_struct *task,
- void __user *from)
-{
- return __copy_from_user(task->thread.ckfp_state.fpr, from,
- ELF_NFPREG * sizeof(double));
-}
-#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
#endif
/* Log an error when sending an unhandled signal to a process. Controlled
diff --git a/arch/powerpc/kernel/signal.h b/arch/powerpc/kernel/signal.h
index d396efca4068..4626d39cc0f0 100644
--- a/arch/powerpc/kernel/signal.h
+++ b/arch/powerpc/kernel/signal.h
@@ -19,14 +19,6 @@ extern int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
extern int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
struct task_struct *tsk);
-extern unsigned long copy_fpr_to_user(void __user *to,
- struct task_struct *task);
-extern unsigned long copy_ckfpr_to_user(void __user *to,
- struct task_struct *task);
-extern unsigned long copy_fpr_from_user(struct task_struct *task,
- void __user *from);
-extern unsigned long copy_ckfpr_from_user(struct task_struct *task,
- void __user *from);
extern unsigned long get_tm_stackpointer(struct task_struct *tsk);
#ifdef CONFIG_VSX
@@ -38,6 +30,39 @@ extern unsigned long copy_vsx_from_user(struct task_struct *task,
void __user *from);
extern unsigned long copy_ckvsx_from_user(struct task_struct *task,
void __user *from);
+unsigned long copy_fpr_to_user(void __user *to, struct task_struct *task);
+unsigned long copy_ckfpr_to_user(void __user *to, struct task_struct *task);
+unsigned long copy_fpr_from_user(struct task_struct *task, void __user *from);
+unsigned long copy_ckfpr_from_user(struct task_struct *task, void __user *from);
+#else
+static inline unsigned long
+copy_fpr_to_user(void __user *to, struct task_struct *task)
+{
+ return __copy_to_user(to, task->thread.fp_state.fpr,
+ ELF_NFPREG * sizeof(double));
+}
+
+static inline unsigned long
+copy_fpr_from_user(struct task_struct *task, void __user *from)
+{
+ return __copy_from_user(task->thread.fp_state.fpr, from,
+ ELF_NFPREG * sizeof(double));
+}
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+inline unsigned long copy_ckfpr_to_user(void __user *to, struct task_struct *task)
+{
+ return __copy_to_user(to, task->thread.ckfp_state.fpr,
+ ELF_NFPREG * sizeof(double));
+}
+
+static inline unsigned long
+copy_ckfpr_from_user(struct task_struct *task, void __user *from)
+{
+ return __copy_from_user(task->thread.ckfp_state.fpr, from,
+ ELF_NFPREG * sizeof(double));
+}
+#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
#endif
#ifdef CONFIG_PPC64
--
2.25.0
^ permalink raw reply related
* [RFC PATCH v1 08/19] powerpc/signal: Remove get_clean_sp()
From: Christophe Leroy @ 2020-08-12 12:05 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, ldv,
viro
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597233555.git.christophe.leroy@csgroup.eu>
get_clean_sp() is only used once in kernel/signal.c .
And GCC is smart enough to see that x & 0xffffffff is a nop
calculation on PPC32, no need of a special PPC32 trivial version.
Include the logic from the PPC64 version of get_clean_sp() directly
in get_sigframe()
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/include/asm/processor.h | 14 --------------
arch/powerpc/kernel/signal.c | 5 ++++-
2 files changed, 4 insertions(+), 15 deletions(-)
diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
index e20b0c5abe62..8320aedbdca3 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -406,20 +406,6 @@ static inline void prefetchw(const void *x)
#define HAVE_ARCH_PICK_MMAP_LAYOUT
-#ifdef CONFIG_PPC64
-static inline unsigned long get_clean_sp(unsigned long sp, int is_32)
-{
- if (is_32)
- return sp & 0x0ffffffffUL;
- return sp;
-}
-#else
-static inline unsigned long get_clean_sp(unsigned long sp, int is_32)
-{
- return sp;
-}
-#endif
-
/* asm stubs */
extern unsigned long isa300_idle_stop_noloss(unsigned long psscr_val);
extern unsigned long isa300_idle_stop_mayloss(unsigned long psscr_val);
diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c
index 1be5fd01f866..a295d482adec 100644
--- a/arch/powerpc/kernel/signal.c
+++ b/arch/powerpc/kernel/signal.c
@@ -150,7 +150,10 @@ void __user *get_sigframe(struct ksignal *ksig, unsigned long sp,
unsigned long oldsp, newsp;
/* Default to using normal stack */
- oldsp = get_clean_sp(sp, is_32);
+ if (is_32)
+ oldsp = sp & 0x0ffffffffUL;
+ else
+ oldsp = sp;
oldsp = sigsp(oldsp, ksig);
newsp = (oldsp - frame_size) & ~0xFUL;
--
2.25.0
^ permalink raw reply related
* [RFC PATCH v1 07/19] powerpc/signal: Move access_ok() out of get_sigframe()
From: Christophe Leroy @ 2020-08-12 12:05 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, ldv,
viro
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597233555.git.christophe.leroy@csgroup.eu>
This access_ok() will soon be performed by user_access_begin().
So move it out of get_sigframe()
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal.c | 4 ----
arch/powerpc/kernel/signal_32.c | 4 ++--
arch/powerpc/kernel/signal_64.c | 2 +-
3 files changed, 3 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c
index 3b56db02b762..1be5fd01f866 100644
--- a/arch/powerpc/kernel/signal.c
+++ b/arch/powerpc/kernel/signal.c
@@ -154,10 +154,6 @@ void __user *get_sigframe(struct ksignal *ksig, unsigned long sp,
oldsp = sigsp(oldsp, ksig);
newsp = (oldsp - frame_size) & ~0xFUL;
- /* Check access */
- if (!access_ok((void __user *)newsp, oldsp - newsp))
- return NULL;
-
return (void __user *)newsp;
}
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 7b291707eb31..5a838188a181 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -770,7 +770,7 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
/* Put a Real Time Context onto stack */
rt_sf = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*rt_sf), 1);
addr = rt_sf;
- if (unlikely(rt_sf == NULL))
+ if (!access_ok(rt_sf, sizeof(*rt_sf)))
goto badframe;
/* Put the siginfo & fill in most of the ucontext */
@@ -1231,7 +1231,7 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
/* Set up Signal Frame */
frame = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*frame), 1);
- if (unlikely(frame == NULL))
+ if (!access_ok(frame, sizeof(*frame)))
goto badframe;
sc = (struct sigcontext __user *) &frame->sctx;
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index bfc939360bad..ec259a0efe24 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -825,7 +825,7 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
BUG_ON(tsk != current);
frame = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*frame), 0);
- if (unlikely(frame == NULL))
+ if (!access_ok(frame, sizeof(*frame)))
goto badframe;
err |= __put_user(&frame->info, &frame->pinfo);
--
2.25.0
^ permalink raw reply related
* [RFC PATCH v1 06/19] powerpc/32s: Allow deselecting CONFIG_PPC_FPU on mpc832x
From: Christophe Leroy @ 2020-08-12 12:05 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, ldv,
viro
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597233555.git.christophe.leroy@csgroup.eu>
The e300c2 core which is embedded in mpc832x CPU doesn't have
an FPU.
Make it possible to not select CONFIG_PPC_FPU when building a
kernel dedicated to that target.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/platforms/Kconfig.cputype | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index 40ffcdba42b8..d4fd109f177e 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -32,7 +32,7 @@ choice
config PPC_BOOK3S_6xx
bool "512x/52xx/6xx/7xx/74xx/82xx/83xx/86xx except 601"
select PPC_BOOK3S_32
- select PPC_FPU
+ imply PPC_FPU
select PPC_HAVE_PMU_SUPPORT
select PPC_HAVE_KUEP
select PPC_HAVE_KUAP
@@ -229,9 +229,16 @@ config PPC_FPU_REGS
bool
config PPC_FPU
- bool
+ bool "Support for Floating Point Unit (FPU)" if PPC_MPC832x
default y if PPC64
select PPC_FPU_REGS
+ help
+ This must be enabled to support the Floating Point Unit
+ Most 6xx have an FPU but e300c2 core (mpc832x) don't have
+ an FPU, so when building an embedded kernel for that target
+ you can disable FPU support.
+
+ If unsure say Y.
config FSL_EMB_PERFMON
bool "Freescale Embedded Perfmon"
--
2.25.0
^ permalink raw reply related
* [RFC PATCH v1 09/19] powerpc/signal: Call get_tm_stackpointer() from get_sigframe()
From: Christophe Leroy @ 2020-08-12 12:06 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, ldv,
viro
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597233555.git.christophe.leroy@csgroup.eu>
Instead of calling get_tm_stackpointer() from the caller, call it
directly from get_sigframe(). This avoids a double call and
allows get_tm_stackpointer() to become static and be inlined
into get_sigframe() by GCC.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal.c | 9 ++++++---
arch/powerpc/kernel/signal.h | 6 ++----
arch/powerpc/kernel/signal_32.c | 4 ++--
arch/powerpc/kernel/signal_64.c | 2 +-
4 files changed, 11 insertions(+), 10 deletions(-)
diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c
index a295d482adec..5edded5c5d20 100644
--- a/arch/powerpc/kernel/signal.c
+++ b/arch/powerpc/kernel/signal.c
@@ -144,10 +144,13 @@ int show_unhandled_signals = 1;
/*
* Allocate space for the signal frame
*/
-void __user *get_sigframe(struct ksignal *ksig, unsigned long sp,
- size_t frame_size, int is_32)
+static unsigned long get_tm_stackpointer(struct task_struct *tsk);
+
+void __user *get_sigframe(struct ksignal *ksig, struct task_struct *tsk,
+ size_t frame_size, int is_32)
{
unsigned long oldsp, newsp;
+ unsigned long sp = get_tm_stackpointer(tsk);
/* Default to using normal stack */
if (is_32)
@@ -304,7 +307,7 @@ void do_notify_resume(struct pt_regs *regs, unsigned long thread_info_flags)
user_enter();
}
-unsigned long get_tm_stackpointer(struct task_struct *tsk)
+static unsigned long get_tm_stackpointer(struct task_struct *tsk)
{
/* When in an active transaction that takes a signal, we need to be
* careful with the stack. It's possible that the stack has moved back
diff --git a/arch/powerpc/kernel/signal.h b/arch/powerpc/kernel/signal.h
index 6c2a33ab042c..fb98731348c3 100644
--- a/arch/powerpc/kernel/signal.h
+++ b/arch/powerpc/kernel/signal.h
@@ -10,8 +10,8 @@
#ifndef _POWERPC_ARCH_SIGNAL_H
#define _POWERPC_ARCH_SIGNAL_H
-extern void __user *get_sigframe(struct ksignal *ksig, unsigned long sp,
- size_t frame_size, int is_32);
+void __user *get_sigframe(struct ksignal *ksig, struct task_struct *tsk,
+ size_t frame_size, int is_32);
extern int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
struct task_struct *tsk);
@@ -19,8 +19,6 @@ extern int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
extern int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
struct task_struct *tsk);
-extern unsigned long get_tm_stackpointer(struct task_struct *tsk);
-
#ifdef CONFIG_VSX
extern unsigned long copy_vsx_to_user(void __user *to,
struct task_struct *task);
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 5a838188a181..3356f6aba4ae 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -768,7 +768,7 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
/* Set up Signal Frame */
/* Put a Real Time Context onto stack */
- rt_sf = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*rt_sf), 1);
+ rt_sf = get_sigframe(ksig, tsk, sizeof(*rt_sf), 1);
addr = rt_sf;
if (!access_ok(rt_sf, sizeof(*rt_sf)))
goto badframe;
@@ -1230,7 +1230,7 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
BUG_ON(tsk != current);
/* Set up Signal Frame */
- frame = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*frame), 1);
+ frame = get_sigframe(ksig, tsk, sizeof(*frame), 1);
if (!access_ok(frame, sizeof(*frame)))
goto badframe;
sc = (struct sigcontext __user *) &frame->sctx;
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index ec259a0efe24..92d152c1155c 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -824,7 +824,7 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
BUG_ON(tsk != current);
- frame = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*frame), 0);
+ frame = get_sigframe(ksig, tsk, sizeof(*frame), 0);
if (!access_ok(frame, sizeof(*frame)))
goto badframe;
--
2.25.0
^ permalink raw reply related
* [RFC PATCH v1 10/19] powerpc/signal: Refactor bad frame logging
From: Christophe Leroy @ 2020-08-12 12:06 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, ldv,
viro
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597233555.git.christophe.leroy@csgroup.eu>
The logging of bad frame appears half a dozen of times
and is pretty similar.
Create signal_fault() fonction to perform that logging.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal.c | 11 +++++++++++
arch/powerpc/kernel/signal.h | 3 +++
arch/powerpc/kernel/signal_32.c | 35 +++++----------------------------
arch/powerpc/kernel/signal_64.c | 15 ++------------
4 files changed, 21 insertions(+), 43 deletions(-)
diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c
index 5edded5c5d20..53b4987a45b5 100644
--- a/arch/powerpc/kernel/signal.c
+++ b/arch/powerpc/kernel/signal.c
@@ -355,3 +355,14 @@ static unsigned long get_tm_stackpointer(struct task_struct *tsk)
#endif
return ret;
}
+
+static const char fmt32[] = KERN_INFO "%s[%d]: bad frame in %s: %p nip %08lx lr %08lx\n";
+static const char fmt64[] = KERN_INFO "%s[%d]: bad frame in %s: %p nip %016lx lr %016lx\n";
+
+void signal_fault(struct task_struct *tsk, struct pt_regs *regs,
+ const char *where, void __user *ptr)
+{
+ if (show_unhandled_signals)
+ printk_ratelimited(regs->msr & MSR_64BIT ? fmt64 : fmt32, tsk->comm,
+ task_pid_nr(tsk), where, ptr, regs->nip, regs->link);
+}
diff --git a/arch/powerpc/kernel/signal.h b/arch/powerpc/kernel/signal.h
index fb98731348c3..f610cfafa478 100644
--- a/arch/powerpc/kernel/signal.h
+++ b/arch/powerpc/kernel/signal.h
@@ -93,4 +93,7 @@ static inline int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
#endif /* !defined(CONFIG_PPC64) */
+void signal_fault(struct task_struct *tsk, struct pt_regs *regs,
+ const char *where, void __user *ptr);
+
#endif /* _POWERPC_ARCH_SIGNAL_H */
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 3356f6aba4ae..d1087dd87174 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -837,12 +837,7 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
return 0;
badframe:
- if (show_unhandled_signals)
- printk_ratelimited(KERN_INFO
- "%s[%d]: bad frame in handle_rt_signal32: "
- "%p nip %08lx lr %08lx\n",
- tsk->comm, tsk->pid,
- addr, regs->nip, regs->link);
+ signal_fault(tsk, regs, "handle_rt_signal32", addr);
return 1;
}
@@ -1094,12 +1089,7 @@ SYSCALL_DEFINE0(rt_sigreturn)
return 0;
bad:
- if (show_unhandled_signals)
- printk_ratelimited(KERN_INFO
- "%s[%d]: bad frame in sys_rt_sigreturn: "
- "%p nip %08lx lr %08lx\n",
- current->comm, current->pid,
- rt_sf, regs->nip, regs->link);
+ signal_fault(current, regs, "sys_rt_sigreturn", rt_sf);
force_sig(SIGSEGV);
return 0;
@@ -1183,12 +1173,7 @@ SYSCALL_DEFINE3(debug_setcontext, struct ucontext __user *, ctx,
* We kill the task with a SIGSEGV in this situation.
*/
if (do_setcontext(ctx, regs, 1)) {
- if (show_unhandled_signals)
- printk_ratelimited(KERN_INFO "%s[%d]: bad frame in "
- "sys_debug_setcontext: %p nip %08lx "
- "lr %08lx\n",
- current->comm, current->pid,
- ctx, regs->nip, regs->link);
+ signal_fault(current, regs, "sys_debug_setcontext", ctx);
force_sig(SIGSEGV);
goto out;
@@ -1291,12 +1276,7 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
return 0;
badframe:
- if (show_unhandled_signals)
- printk_ratelimited(KERN_INFO
- "%s[%d]: bad frame in handle_signal32: "
- "%p nip %08lx lr %08lx\n",
- tsk->comm, tsk->pid,
- frame, regs->nip, regs->link);
+ signal_fault(tsk, regs, "handle_signal32", frame);
return 1;
}
@@ -1367,12 +1347,7 @@ SYSCALL_DEFINE0(sigreturn)
return 0;
badframe:
- if (show_unhandled_signals)
- printk_ratelimited(KERN_INFO
- "%s[%d]: bad frame in sys_sigreturn: "
- "%p nip %08lx lr %08lx\n",
- current->comm, current->pid,
- addr, regs->nip, regs->link);
+ signal_fault(current, regs, "sys_sigreturn", addr);
force_sig(SIGSEGV);
return 0;
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index 92d152c1155c..a10b0bb14131 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -66,11 +66,6 @@ struct rt_sigframe {
char abigap[USER_REDZONE_SIZE];
} __attribute__ ((aligned (16)));
-static const char fmt32[] = KERN_INFO \
- "%s[%d]: bad frame in %s: %08lx nip %08lx lr %08lx\n";
-static const char fmt64[] = KERN_INFO \
- "%s[%d]: bad frame in %s: %016lx nip %016lx lr %016lx\n";
-
/*
* This computes a quad word aligned pointer inside the vmx_reserve array
* element. For historical reasons sigcontext might not be quad word aligned,
@@ -801,10 +796,7 @@ SYSCALL_DEFINE0(rt_sigreturn)
return 0;
badframe:
- if (show_unhandled_signals)
- printk_ratelimited(regs->msr & MSR_64BIT ? fmt64 : fmt32,
- current->comm, current->pid, "rt_sigreturn",
- (long)uc, regs->nip, regs->link);
+ signal_fault(current, regs, "rt_sigreturn", uc);
force_sig(SIGSEGV);
return 0;
@@ -913,10 +905,7 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
return 0;
badframe:
- if (show_unhandled_signals)
- printk_ratelimited(regs->msr & MSR_64BIT ? fmt64 : fmt32,
- tsk->comm, tsk->pid, "setup_rt_frame",
- (long)frame, regs->nip, regs->link);
+ signal_fault(current, regs, "handle_rt_signal64", frame);
return 1;
}
--
2.25.0
^ permalink raw reply related
* [RFC PATCH v1 05/19] powerpc/signal: Don't manage floating point regs when no FPU
From: Christophe Leroy @ 2020-08-12 12:05 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, ldv,
viro
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597233555.git.christophe.leroy@csgroup.eu>
There is no point in copying floating point regs when there
is no FPU and MATH_EMULATION is not selected.
Create a new CONFIG_PPC_FPU_REGS bool that is selected by
CONFIG_MATH_EMULATION and CONFIG_PPC_FPU, and use it to
opt out everything related to fp_state in thread_struct.
The asm const used only by fpu.S are opted out with CONFIG_PPC_FPU
as fpu.S build is conditionnal to CONFIG_PPC_FPU.
The following app spends approx 8.1 seconds system time on
an 8xx without the patch, and 7.0 seconds with the patch.
void sigusr1(int sig) { }
int main(int argc, char **argv)
{
int i = 100000;
signal(SIGUSR1, sigusr1);
for (;i--;)
raise(SIGUSR1);
exit(0);
}
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/Kconfig | 1 +
arch/powerpc/include/asm/processor.h | 2 ++
arch/powerpc/kernel/asm-offsets.c | 2 ++
arch/powerpc/kernel/process.c | 4 ++++
arch/powerpc/kernel/ptrace/Makefile | 4 ++--
arch/powerpc/kernel/ptrace/ptrace-decl.h | 14 ++++++++++++++
arch/powerpc/kernel/ptrace/ptrace-view.c | 2 ++
arch/powerpc/kernel/signal.h | 14 +++++++++++++-
arch/powerpc/kernel/signal_32.c | 4 ++++
arch/powerpc/kernel/traps.c | 2 ++
arch/powerpc/platforms/Kconfig.cputype | 4 ++++
11 files changed, 50 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 1f48bbfb3ce9..a2611880b904 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -416,6 +416,7 @@ config HUGETLB_PAGE_SIZE_VARIABLE
config MATH_EMULATION
bool "Math emulation"
depends on 4xx || PPC_8xx || PPC_MPC832x || BOOKE
+ select PPC_FPU_REGS
help
Some PowerPC chips designed for embedded applications do not have
a floating-point unit and therefore do not implement the
diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
index ed0d633ab5aa..e20b0c5abe62 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -175,8 +175,10 @@ struct thread_struct {
#endif
/* Debug Registers */
struct debug_reg debug;
+#ifdef CONFIG_PPC_FPU_REGS
struct thread_fp_state fp_state;
struct thread_fp_state *fp_save_area;
+#endif
int fpexc_mode; /* floating-point exception mode */
unsigned int align_ctl; /* alignment handling control */
#ifdef CONFIG_HAVE_HW_BREAKPOINT
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 8711c2164b45..6cb36c341c70 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -110,9 +110,11 @@ int main(void)
#ifdef CONFIG_BOOKE
OFFSET(THREAD_NORMSAVES, thread_struct, normsave[0]);
#endif
+#ifdef CONFIG_PPC_FPU
OFFSET(THREAD_FPEXC_MODE, thread_struct, fpexc_mode);
OFFSET(THREAD_FPSTATE, thread_struct, fp_state.fpr);
OFFSET(THREAD_FPSAVEAREA, thread_struct, fp_save_area);
+#endif
OFFSET(FPSTATE_FPSCR, thread_fp_state, fpscr);
OFFSET(THREAD_LOAD_FP, thread_struct, load_fp);
#ifdef CONFIG_ALTIVEC
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 016bd831908e..7e0082ac0a39 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1694,7 +1694,9 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
p->thread.ptrace_bps[i] = NULL;
#endif
+#ifdef CONFIG_PPC_FPU_REGS
p->thread.fp_save_area = NULL;
+#endif
#ifdef CONFIG_ALTIVEC
p->thread.vr_save_area = NULL;
#endif
@@ -1821,8 +1823,10 @@ void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
#endif
current->thread.load_slb = 0;
current->thread.load_fp = 0;
+#ifdef CONFIG_PPC_FPU_REGS
memset(¤t->thread.fp_state, 0, sizeof(current->thread.fp_state));
current->thread.fp_save_area = NULL;
+#endif
#ifdef CONFIG_ALTIVEC
memset(¤t->thread.vr_state, 0, sizeof(current->thread.vr_state));
current->thread.vr_state.vscr.u[3] = 0x00010000; /* Java mode disabled */
diff --git a/arch/powerpc/kernel/ptrace/Makefile b/arch/powerpc/kernel/ptrace/Makefile
index 77abd1a5a508..8ebc11d1168d 100644
--- a/arch/powerpc/kernel/ptrace/Makefile
+++ b/arch/powerpc/kernel/ptrace/Makefile
@@ -6,11 +6,11 @@
CFLAGS_ptrace-view.o += -DUTS_MACHINE='"$(UTS_MACHINE)"'
obj-y += ptrace.o ptrace-view.o
-obj-y += ptrace-fpu.o
+obj-$(CONFIG_PPC_FPU_REGS) += ptrace-fpu.o
obj-$(CONFIG_COMPAT) += ptrace32.o
obj-$(CONFIG_VSX) += ptrace-vsx.o
ifneq ($(CONFIG_VSX),y)
-obj-y += ptrace-novsx.o
+obj-$(CONFIG_PPC_FPU_REGS) += ptrace-novsx.o
endif
obj-$(CONFIG_ALTIVEC) += ptrace-altivec.o
obj-$(CONFIG_SPE) += ptrace-spe.o
diff --git a/arch/powerpc/kernel/ptrace/ptrace-decl.h b/arch/powerpc/kernel/ptrace/ptrace-decl.h
index eafe5f0f6289..3487f2c9735c 100644
--- a/arch/powerpc/kernel/ptrace/ptrace-decl.h
+++ b/arch/powerpc/kernel/ptrace/ptrace-decl.h
@@ -165,8 +165,22 @@ int ptrace_put_reg(struct task_struct *task, int regno, unsigned long data);
extern const struct user_regset_view user_ppc_native_view;
/* ptrace-fpu */
+#ifdef CONFIG_PPC_FPU_REGS
int ptrace_get_fpr(struct task_struct *child, int index, unsigned long *data);
int ptrace_put_fpr(struct task_struct *child, int index, unsigned long data);
+#else
+static inline int
+ptrace_get_fpr(struct task_struct *child, int index, unsigned long *data)
+{
+ return -EIO;
+}
+
+static inline int
+ptrace_put_fpr(struct task_struct *child, int index, unsigned long data)
+{
+ return -EIO;
+}
+#endif
/* ptrace-(no)adv */
void ppc_gethwdinfo(struct ppc_debug_info *dbginfo);
diff --git a/arch/powerpc/kernel/ptrace/ptrace-view.c b/arch/powerpc/kernel/ptrace/ptrace-view.c
index 7e6478e7ed07..f1df8c62baf1 100644
--- a/arch/powerpc/kernel/ptrace/ptrace-view.c
+++ b/arch/powerpc/kernel/ptrace/ptrace-view.c
@@ -520,11 +520,13 @@ static const struct user_regset native_regsets[] = {
.size = sizeof(long), .align = sizeof(long),
.regset_get = gpr_get, .set = gpr_set
},
+#ifdef CONFIG_PPC_FPU_REGS
[REGSET_FPR] = {
.core_note_type = NT_PRFPREG, .n = ELF_NFPREG,
.size = sizeof(double), .align = sizeof(double),
.regset_get = fpr_get, .set = fpr_set
},
+#endif
#ifdef CONFIG_ALTIVEC
[REGSET_VMX] = {
.core_note_type = NT_PPC_VMX, .n = 34,
diff --git a/arch/powerpc/kernel/signal.h b/arch/powerpc/kernel/signal.h
index 4626d39cc0f0..6c2a33ab042c 100644
--- a/arch/powerpc/kernel/signal.h
+++ b/arch/powerpc/kernel/signal.h
@@ -34,7 +34,7 @@ unsigned long copy_fpr_to_user(void __user *to, struct task_struct *task);
unsigned long copy_ckfpr_to_user(void __user *to, struct task_struct *task);
unsigned long copy_fpr_from_user(struct task_struct *task, void __user *from);
unsigned long copy_ckfpr_from_user(struct task_struct *task, void __user *from);
-#else
+#elif defined(CONFIG_PPC_FPU_REGS)
static inline unsigned long
copy_fpr_to_user(void __user *to, struct task_struct *task)
{
@@ -63,6 +63,18 @@ copy_ckfpr_from_user(struct task_struct *task, void __user *from)
ELF_NFPREG * sizeof(double));
}
#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
+#else
+static inline unsigned long
+copy_fpr_to_user(void __user *to, struct task_struct *task)
+{
+ return 0;
+}
+
+static inline unsigned long
+copy_fpr_from_user(struct task_struct *task, void __user *from)
+{
+ return 0;
+}
#endif
#ifdef CONFIG_PPC64
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 96950f189b5a..7b291707eb31 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -814,7 +814,9 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
}
regs->link = tramp;
+#ifdef CONFIG_PPC_FPU_REGS
tsk->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
+#endif
/* create a stack frame for the caller of the handler */
newsp = ((unsigned long)rt_sf) - (__SIGNAL_FRAMESIZE + 16);
@@ -1271,7 +1273,9 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
regs->link = tramp;
+#ifdef CONFIG_PPC_FPU_REGS
tsk->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
+#endif
/* create a stack frame for the caller of the handler */
newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index d1ebe152f210..5c68f0de905c 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -1194,7 +1194,9 @@ static void parse_fpe(struct pt_regs *regs)
flush_fp_to_thread(current);
+#ifdef CONFIG_PPC_FPU_REGS
code = __parse_fpscr(current->thread.fp_state.fpscr);
+#endif
_exception(SIGFPE, regs, code, regs->nip);
}
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index 87737ec86d39..40ffcdba42b8 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -225,9 +225,13 @@ config PPC_E500MC
such as e5500/e6500), and must be disabled for running on
e500v1 or e500v2.
+config PPC_FPU_REGS
+ bool
+
config PPC_FPU
bool
default y if PPC64
+ select PPC_FPU_REGS
config FSL_EMB_PERFMON
bool "Freescale Embedded Perfmon"
--
2.25.0
^ permalink raw reply related
* [RFC PATCH v1 12/19] powerpc/signal32: Regroup copies in save_user_regs() and save_tm_user_regs()
From: Christophe Leroy @ 2020-08-12 12:06 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, ldv,
viro
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597233555.git.christophe.leroy@csgroup.eu>
Reorder actions in save_user_regs() and save_tm_user_regs() to
regroup copies together in order to switch to user_access_begin()
logic in a later patch.
In save_tm_user_regs(), first perform copies to frame, then
perform copies to tm_frame.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal_32.c | 153 +++++++++++++++++++-------------
1 file changed, 91 insertions(+), 62 deletions(-)
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 495bee1b713d..2c3d5d4400ec 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -243,6 +243,20 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
/* Make sure floating point registers are stored in regs */
flush_fp_to_thread(current);
+#ifdef CONFIG_ALTIVEC
+ if (current->thread.used_vr)
+ flush_altivec_to_thread(current);
+ if (cpu_has_feature(CPU_FTR_ALTIVEC))
+ current->thread.vrsave = mfspr(SPRN_VRSAVE);
+#endif
+#ifdef CONFIG_VSX
+ if (current->thread.used_vsr && ctx_has_vsx_region)
+ flush_vsx_to_thread(current);
+#endif
+#ifdef CONFIG_SPE
+ if (current->thread.used_spe)
+ flush_spe_to_thread(current);
+#endif
/* save general registers */
if (save_general_regs(regs, frame))
@@ -251,7 +265,6 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
#ifdef CONFIG_ALTIVEC
/* save altivec registers */
if (current->thread.used_vr) {
- flush_altivec_to_thread(current);
if (__copy_to_user(&frame->mc_vregs, ¤t->thread.vr_state,
ELF_NVRREG * sizeof(vector128)))
return 1;
@@ -267,8 +280,6 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
* most significant bits of that same vector. --BenH
* Note that the current VRSAVE value is in the SPR at this point.
*/
- if (cpu_has_feature(CPU_FTR_ALTIVEC))
- current->thread.vrsave = mfspr(SPRN_VRSAVE);
if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32]))
return 1;
#endif /* CONFIG_ALTIVEC */
@@ -288,7 +299,6 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
* contains valid data
*/
if (current->thread.used_vsr && ctx_has_vsx_region) {
- flush_vsx_to_thread(current);
if (copy_vsx_to_user(&frame->mc_vsregs, current))
return 1;
msr |= MSR_VSX;
@@ -297,7 +307,6 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
#ifdef CONFIG_SPE
/* save spe registers */
if (current->thread.used_spe) {
- flush_spe_to_thread(current);
if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
ELF_NEVRREG * sizeof(u32)))
return 1;
@@ -314,20 +323,22 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
return 1;
- /* We need to write 0 the MSR top 32 bits in the tm frame so that we
- * can check it on the restore to see if TM is active
- */
- if (tm_frame && __put_user(0, &tm_frame->mc_gregs[PT_MSR]))
- return 1;
if (sigret) {
/* Set up the sigreturn trampoline: li 0,sigret; sc */
if (__put_user(PPC_INST_ADDI + sigret, &frame->tramp[0])
|| __put_user(PPC_INST_SC, &frame->tramp[1]))
return 1;
+ }
+ if (sigret)
flush_icache_range((unsigned long) &frame->tramp[0],
(unsigned long) &frame->tramp[2]);
- }
+
+ /* We need to write 0 the MSR top 32 bits in the tm frame so that we
+ * can check it on the restore to see if TM is active
+ */
+ if (tm_frame && __put_user(0, &tm_frame->mc_gregs[PT_MSR]))
+ return 1;
return 0;
}
@@ -349,18 +360,16 @@ static int save_tm_user_regs(struct pt_regs *regs,
{
WARN_ON(tm_suspend_disabled);
- /* Save both sets of general registers */
- if (save_general_regs(¤t->thread.ckpt_regs, frame)
- || save_general_regs(regs, tm_frame))
- return 1;
+#ifdef CONFIG_ALTIVEC
+ if (cpu_has_feature(CPU_FTR_ALTIVEC))
+ current->thread.ckvrsave = mfspr(SPRN_VRSAVE);
+#endif
+#ifdef CONFIG_SPE
+ if (current->thread.used_spe)
+ flush_spe_to_thread(current);
+#endif
- /* Stash the top half of the 64bit MSR into the 32bit MSR word
- * of the transactional mcontext. This way we have a backward-compatible
- * MSR in the 'normal' (checkpointed) mcontext and additionally one can
- * also look at what type of transaction (T or S) was active at the
- * time of the signal.
- */
- if (__put_user((msr >> 32), &tm_frame->mc_gregs[PT_MSR]))
+ if (save_general_regs(¤t->thread.ckpt_regs, frame))
return 1;
#ifdef CONFIG_ALTIVEC
@@ -369,17 +378,6 @@ static int save_tm_user_regs(struct pt_regs *regs,
if (__copy_to_user(&frame->mc_vregs, ¤t->thread.ckvr_state,
ELF_NVRREG * sizeof(vector128)))
return 1;
- if (msr & MSR_VEC) {
- if (__copy_to_user(&tm_frame->mc_vregs,
- ¤t->thread.vr_state,
- ELF_NVRREG * sizeof(vector128)))
- return 1;
- } else {
- if (__copy_to_user(&tm_frame->mc_vregs,
- ¤t->thread.ckvr_state,
- ELF_NVRREG * sizeof(vector128)))
- return 1;
- }
/* set MSR_VEC in the saved MSR value to indicate that
* frame->mc_vregs contains valid data
@@ -392,32 +390,13 @@ static int save_tm_user_regs(struct pt_regs *regs,
* significant bits of a vector, we "cheat" and stuff VRSAVE in the
* most significant bits of that same vector. --BenH
*/
- if (cpu_has_feature(CPU_FTR_ALTIVEC))
- current->thread.ckvrsave = mfspr(SPRN_VRSAVE);
if (__put_user(current->thread.ckvrsave,
(u32 __user *)&frame->mc_vregs[32]))
return 1;
- if (msr & MSR_VEC) {
- if (__put_user(current->thread.vrsave,
- (u32 __user *)&tm_frame->mc_vregs[32]))
- return 1;
- } else {
- if (__put_user(current->thread.ckvrsave,
- (u32 __user *)&tm_frame->mc_vregs[32]))
- return 1;
- }
#endif /* CONFIG_ALTIVEC */
if (copy_ckfpr_to_user(&frame->mc_fregs, current))
return 1;
- if (msr & MSR_FP) {
- if (copy_fpr_to_user(&tm_frame->mc_fregs, current))
- return 1;
- } else {
- if (copy_ckfpr_to_user(&tm_frame->mc_fregs, current))
- return 1;
- }
-
#ifdef CONFIG_VSX
/*
* Copy VSR 0-31 upper half from thread_struct to local
@@ -428,15 +407,6 @@ static int save_tm_user_regs(struct pt_regs *regs,
if (current->thread.used_vsr) {
if (copy_ckvsx_to_user(&frame->mc_vsregs, current))
return 1;
- if (msr & MSR_VSX) {
- if (copy_vsx_to_user(&tm_frame->mc_vsregs,
- current))
- return 1;
- } else {
- if (copy_ckvsx_to_user(&tm_frame->mc_vsregs, current))
- return 1;
- }
-
msr |= MSR_VSX;
}
#endif /* CONFIG_VSX */
@@ -445,7 +415,6 @@ static int save_tm_user_regs(struct pt_regs *regs,
* simply the same as in save_user_regs().
*/
if (current->thread.used_spe) {
- flush_spe_to_thread(current);
if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
ELF_NEVRREG * sizeof(u32)))
return 1;
@@ -466,9 +435,69 @@ static int save_tm_user_regs(struct pt_regs *regs,
if (__put_user(PPC_INST_ADDI + sigret, &frame->tramp[0])
|| __put_user(PPC_INST_SC, &frame->tramp[1]))
return 1;
+ }
+ if (sigret)
flush_icache_range((unsigned long) &frame->tramp[0],
(unsigned long) &frame->tramp[2]);
+
+ if (save_general_regs(regs, tm_frame))
+ return 1;
+
+ /* Stash the top half of the 64bit MSR into the 32bit MSR word
+ * of the transactional mcontext. This way we have a backward-compatible
+ * MSR in the 'normal' (checkpointed) mcontext and additionally one can
+ * also look at what type of transaction (T or S) was active at the
+ * time of the signal.
+ */
+ if (__put_user((msr >> 32), &tm_frame->mc_gregs[PT_MSR]))
+ return 1;
+
+#ifdef CONFIG_ALTIVEC
+ if (current->thread.used_vr) {
+ if (msr & MSR_VEC) {
+ if (__copy_to_user(&tm_frame->mc_vregs,
+ ¤t->thread.vr_state,
+ ELF_NVRREG * sizeof(vector128)))
+ return 1;
+ } else {
+ if (__copy_to_user(&tm_frame->mc_vregs,
+ ¤t->thread.ckvr_state,
+ ELF_NVRREG * sizeof(vector128)))
+ return 1;
+ }
+ }
+
+ if (msr & MSR_VEC) {
+ if (__put_user(current->thread.vrsave,
+ (u32 __user *)&tm_frame->mc_vregs[32]))
+ return 1;
+ } else {
+ if (__put_user(current->thread.ckvrsave,
+ (u32 __user *)&tm_frame->mc_vregs[32]))
+ return 1;
}
+#endif /* CONFIG_ALTIVEC */
+
+ if (msr & MSR_FP) {
+ if (copy_fpr_to_user(&tm_frame->mc_fregs, current))
+ return 1;
+ } else {
+ if (copy_ckfpr_to_user(&tm_frame->mc_fregs, current))
+ return 1;
+ }
+
+#ifdef CONFIG_VSX
+ if (current->thread.used_vsr) {
+ if (msr & MSR_VSX) {
+ if (copy_vsx_to_user(&tm_frame->mc_vsregs,
+ current))
+ return 1;
+ } else {
+ if (copy_ckvsx_to_user(&tm_frame->mc_vsregs, current))
+ return 1;
+ }
+ }
+#endif /* CONFIG_VSX */
return 0;
}
--
2.25.0
^ permalink raw reply related
* [RFC PATCH v1 13/19] powerpc/signal32: Create 'unsafe' versions of copy_[ck][fpr/vsx]_to_user()
From: Christophe Leroy @ 2020-08-12 12:06 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, ldv,
viro
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597233555.git.christophe.leroy@csgroup.eu>
For the non VSX version, that's trivial. Just use unsafe_copy_to_user()
instead of __copy_to_user().
For the VSX version, remove the intermediate step through a buffer and
use unsafe_put_user() directly. This generates a far smaller code which
is acceptable to inline, see below:
Standard VSX version:
0000000000000000 <.copy_fpr_to_user>:
0: 7c 08 02 a6 mflr r0
4: fb e1 ff f8 std r31,-8(r1)
8: 39 00 00 20 li r8,32
c: 39 24 0b 80 addi r9,r4,2944
10: 7d 09 03 a6 mtctr r8
14: f8 01 00 10 std r0,16(r1)
18: f8 21 fe 71 stdu r1,-400(r1)
1c: 39 41 00 68 addi r10,r1,104
20: e9 09 00 00 ld r8,0(r9)
24: 39 4a 00 08 addi r10,r10,8
28: 39 29 00 10 addi r9,r9,16
2c: f9 0a 00 00 std r8,0(r10)
30: 42 00 ff f0 bdnz 20 <.copy_fpr_to_user+0x20>
34: e9 24 0d 80 ld r9,3456(r4)
38: 3d 42 00 00 addis r10,r2,0
3a: R_PPC64_TOC16_HA .toc
3c: eb ea 00 00 ld r31,0(r10)
3e: R_PPC64_TOC16_LO_DS .toc
40: f9 21 01 70 std r9,368(r1)
44: e9 3f 00 00 ld r9,0(r31)
48: 81 29 00 20 lwz r9,32(r9)
4c: 2f 89 00 00 cmpwi cr7,r9,0
50: 40 9c 00 18 bge cr7,68 <.copy_fpr_to_user+0x68>
54: 4c 00 01 2c isync
58: 3d 20 40 00 lis r9,16384
5c: 79 29 07 c6 rldicr r9,r9,32,31
60: 7d 3d 03 a6 mtspr 29,r9
64: 4c 00 01 2c isync
68: 38 a0 01 08 li r5,264
6c: 38 81 00 70 addi r4,r1,112
70: 48 00 00 01 bl 70 <.copy_fpr_to_user+0x70>
70: R_PPC64_REL24 .__copy_tofrom_user
74: 60 00 00 00 nop
78: e9 3f 00 00 ld r9,0(r31)
7c: 81 29 00 20 lwz r9,32(r9)
80: 2f 89 00 00 cmpwi cr7,r9,0
84: 40 9c 00 18 bge cr7,9c <.copy_fpr_to_user+0x9c>
88: 4c 00 01 2c isync
8c: 39 20 ff ff li r9,-1
90: 79 29 00 44 rldicr r9,r9,0,1
94: 7d 3d 03 a6 mtspr 29,r9
98: 4c 00 01 2c isync
9c: 38 21 01 90 addi r1,r1,400
a0: e8 01 00 10 ld r0,16(r1)
a4: eb e1 ff f8 ld r31,-8(r1)
a8: 7c 08 03 a6 mtlr r0
ac: 4e 80 00 20 blr
'unsafe' simulated VSX version (The ... are only nops) using
unsafe_copy_fpr_to_user() macro:
unsigned long copy_fpr_to_user(void __user *to,
struct task_struct *task)
{
unsafe_copy_fpr_to_user(to, task, failed);
return 0;
failed:
return 1;
}
0000000000000000 <.copy_fpr_to_user>:
0: 39 00 00 20 li r8,32
4: 39 44 0b 80 addi r10,r4,2944
8: 7d 09 03 a6 mtctr r8
c: 7c 69 1b 78 mr r9,r3
...
20: e9 0a 00 00 ld r8,0(r10)
24: f9 09 00 00 std r8,0(r9)
28: 39 4a 00 10 addi r10,r10,16
2c: 39 29 00 08 addi r9,r9,8
30: 42 00 ff f0 bdnz 20 <.copy_fpr_to_user+0x20>
34: e9 24 0d 80 ld r9,3456(r4)
38: f9 23 01 00 std r9,256(r3)
3c: 38 60 00 00 li r3,0
40: 4e 80 00 20 blr
...
50: 38 60 00 01 li r3,1
54: 4e 80 00 20 blr
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal.h | 47 ++++++++++++++++++++++++++++++++++++
1 file changed, 47 insertions(+)
diff --git a/arch/powerpc/kernel/signal.h b/arch/powerpc/kernel/signal.h
index f610cfafa478..abe570f06c12 100644
--- a/arch/powerpc/kernel/signal.h
+++ b/arch/powerpc/kernel/signal.h
@@ -32,7 +32,49 @@ unsigned long copy_fpr_to_user(void __user *to, struct task_struct *task);
unsigned long copy_ckfpr_to_user(void __user *to, struct task_struct *task);
unsigned long copy_fpr_from_user(struct task_struct *task, void __user *from);
unsigned long copy_ckfpr_from_user(struct task_struct *task, void __user *from);
+
+#define unsafe_copy_fpr_to_user(to, task, label) do { \
+ u64 __user *buf = (u64 __user *)to; \
+ int i; \
+ \
+ for (i = 0; i < ELF_NFPREG - 1 ; i++) \
+ unsafe_put_user(task->thread.TS_FPR(i), &buf[i], label);\
+ unsafe_put_user(task->thread.fp_state.fpscr, &buf[i], label); \
+} while (0)
+
+#define unsafe_copy_vsx_to_user(to, task, label) do { \
+ u64 __user *buf = (u64 __user *)to; \
+ int i; \
+ \
+ for (i = 0; i < ELF_NVSRHALFREG ; i++) \
+ unsafe_put_user(task->thread.fp_state.fpr[i][TS_VSRLOWOFFSET], \
+ &buf[i], label);\
+} while (0)
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+#define unsafe_copy_ckfpr_to_user(to, task, label) do { \
+ u64 __user *buf = (u64 __user *)to; \
+ int i; \
+ \
+ for (i = 0; i < ELF_NFPREG - 1 ; i++) \
+ unsafe_put_user(task->thread.TS_CKFPR(i), &buf[i], label);\
+ unsafe_put_user(task->thread.ckfp_state.fpscr, &buf[i], label); \
+} while (0)
+
+#define unsafe_copy_ckvsx_to_user(to, task, label) do { \
+ u64 __user *buf = (u64 __user *)to; \
+ int i; \
+ \
+ for (i = 0; i < ELF_NVSRHALFREG ; i++) \
+ unsafe_put_user(task->thread.ckfp_state.fpr[i][TS_VSRLOWOFFSET], \
+ &buf[i], label);\
+} while (0)
+#endif
#elif defined(CONFIG_PPC_FPU_REGS)
+
+#define unsafe_copy_fpr_to_user(to, task, label) \
+ unsafe_copy_to_user(to, task->thread.fp_state.fpr, ELF_NFPREG * sizeof(double), label)
+
static inline unsigned long
copy_fpr_to_user(void __user *to, struct task_struct *task)
{
@@ -48,6 +90,9 @@ copy_fpr_from_user(struct task_struct *task, void __user *from)
}
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+#define unsafe_copy_ckfpr_to_user(to, task, label) \
+ unsafe_copy_to_user(to, task->thread.ckfp_state.fpr, ELF_NFPREG * sizeof(double), label)
+
inline unsigned long copy_ckfpr_to_user(void __user *to, struct task_struct *task)
{
return __copy_to_user(to, task->thread.ckfp_state.fpr,
@@ -62,6 +107,8 @@ copy_ckfpr_from_user(struct task_struct *task, void __user *from)
}
#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
#else
+#define unsafe_copy_fpr_to_user(to, task, label) do { } while (0)
+
static inline unsigned long
copy_fpr_to_user(void __user *to, struct task_struct *task)
{
--
2.25.0
^ permalink raw reply related
* [RFC PATCH v1 14/19] powerpc/signal32: Switch save_user_regs() and save_tm_user_regs() to user_access_begin() logic
From: Christophe Leroy @ 2020-08-12 12:06 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, ldv,
viro
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597233555.git.christophe.leroy@csgroup.eu>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal_32.c | 168 ++++++++++++++++----------------
1 file changed, 84 insertions(+), 84 deletions(-)
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 2c3d5d4400ec..0d076c2a9f6c 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -98,7 +98,7 @@ static inline int get_sigset_t(sigset_t *set,
#define to_user_ptr(p) ptr_to_compat(p)
#define from_user_ptr(p) compat_ptr(p)
-static inline int save_general_regs(struct pt_regs *regs,
+static __always_inline int save_general_regs(struct pt_regs *regs,
struct mcontext __user *frame)
{
elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
@@ -113,10 +113,12 @@ static inline int save_general_regs(struct pt_regs *regs,
else
val = gregs[i];
- if (__put_user(val, &frame->mc_gregs[i]))
- return -EFAULT;
+ unsafe_put_user(val, &frame->mc_gregs[i], failed);
}
return 0;
+
+failed:
+ return 1;
}
static inline int restore_general_regs(struct pt_regs *regs,
@@ -151,11 +153,15 @@ static inline int get_sigset_t(sigset_t *set, const sigset_t __user *uset)
#define to_user_ptr(p) ((unsigned long)(p))
#define from_user_ptr(p) ((void __user *)(p))
-static inline int save_general_regs(struct pt_regs *regs,
+static __always_inline int save_general_regs(struct pt_regs *regs,
struct mcontext __user *frame)
{
WARN_ON(!FULL_REGS(regs));
- return __copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE);
+ unsafe_copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE, failed);
+ return 0;
+
+failed:
+ return 1;
}
static inline int restore_general_regs(struct pt_regs *regs,
@@ -258,16 +264,18 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
flush_spe_to_thread(current);
#endif
+ if (!user_write_access_begin(frame, sizeof(*frame)))
+ return 1;
+
/* save general registers */
if (save_general_regs(regs, frame))
- return 1;
+ goto failed;
#ifdef CONFIG_ALTIVEC
/* save altivec registers */
if (current->thread.used_vr) {
- if (__copy_to_user(&frame->mc_vregs, ¤t->thread.vr_state,
- ELF_NVRREG * sizeof(vector128)))
- return 1;
+ unsafe_copy_to_user(&frame->mc_vregs, ¤t->thread.vr_state,
+ ELF_NVRREG * sizeof(vector128), failed);
/* set MSR_VEC in the saved MSR value to indicate that
frame->mc_vregs contains valid data */
msr |= MSR_VEC;
@@ -280,11 +288,9 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
* most significant bits of that same vector. --BenH
* Note that the current VRSAVE value is in the SPR at this point.
*/
- if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32]))
- return 1;
+ unsafe_put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32], failed);
#endif /* CONFIG_ALTIVEC */
- if (copy_fpr_to_user(&frame->mc_fregs, current))
- return 1;
+ unsafe_copy_fpr_to_user(&frame->mc_fregs, current, failed);
/*
* Clear the MSR VSX bit to indicate there is no valid state attached
@@ -299,17 +305,15 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
* contains valid data
*/
if (current->thread.used_vsr && ctx_has_vsx_region) {
- if (copy_vsx_to_user(&frame->mc_vsregs, current))
- return 1;
+ unsafe_copy_vsx_to_user(&frame->mc_vsregs, current, failed);
msr |= MSR_VSX;
}
#endif /* CONFIG_VSX */
#ifdef CONFIG_SPE
/* save spe registers */
if (current->thread.used_spe) {
- if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
- ELF_NEVRREG * sizeof(u32)))
- return 1;
+ unsafe_copy_to_user(&frame->mc_vregs, current->thread.evr,
+ ELF_NEVRREG * sizeof(u32)), failed);
/* set MSR_SPE in the saved MSR value to indicate that
frame->mc_vregs contains valid data */
msr |= MSR_SPE;
@@ -317,19 +321,18 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
/* else assert((regs->msr & MSR_SPE) == 0) */
/* We always copy to/from spefscr */
- if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
- return 1;
+ unsafe_put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG, failed);
#endif /* CONFIG_SPE */
- if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
- return 1;
+ unsafe_put_user(msr, &frame->mc_gregs[PT_MSR], failed);
if (sigret) {
/* Set up the sigreturn trampoline: li 0,sigret; sc */
- if (__put_user(PPC_INST_ADDI + sigret, &frame->tramp[0])
- || __put_user(PPC_INST_SC, &frame->tramp[1]))
- return 1;
+ unsafe_put_user(PPC_INST_ADDI + sigret, &frame->tramp[0], failed);
+ unsafe_put_user(PPC_INST_SC, &frame->tramp[1], failed);
}
+ user_write_access_end();
+
if (sigret)
flush_icache_range((unsigned long) &frame->tramp[0],
(unsigned long) &frame->tramp[2]);
@@ -341,6 +344,10 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
return 1;
return 0;
+
+failed:
+ user_write_access_end();
+ return 1;
}
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
@@ -369,15 +376,17 @@ static int save_tm_user_regs(struct pt_regs *regs,
flush_spe_to_thread(current);
#endif
- if (save_general_regs(¤t->thread.ckpt_regs, frame))
+ if (!user_write_access_begin(frame, sizeof(*frame)))
return 1;
+ if (save_general_regs(¤t->thread.ckpt_regs, frame))
+ goto failed;
+
#ifdef CONFIG_ALTIVEC
/* save altivec registers */
if (current->thread.used_vr) {
- if (__copy_to_user(&frame->mc_vregs, ¤t->thread.ckvr_state,
- ELF_NVRREG * sizeof(vector128)))
- return 1;
+ unsafe_copy_to_user(&frame->mc_vregs, ¤t->thread.ckvr_state,
+ ELF_NVRREG * sizeof(vector128), failed);
/* set MSR_VEC in the saved MSR value to indicate that
* frame->mc_vregs contains valid data
@@ -390,13 +399,11 @@ static int save_tm_user_regs(struct pt_regs *regs,
* significant bits of a vector, we "cheat" and stuff VRSAVE in the
* most significant bits of that same vector. --BenH
*/
- if (__put_user(current->thread.ckvrsave,
- (u32 __user *)&frame->mc_vregs[32]))
- return 1;
+ unsafe_put_user(current->thread.ckvrsave,
+ (u32 __user *)&frame->mc_vregs[32], failed);
#endif /* CONFIG_ALTIVEC */
- if (copy_ckfpr_to_user(&frame->mc_fregs, current))
- return 1;
+ unsafe_copy_ckfpr_to_user(&frame->mc_fregs, current, failed);
#ifdef CONFIG_VSX
/*
* Copy VSR 0-31 upper half from thread_struct to local
@@ -405,8 +412,7 @@ static int save_tm_user_regs(struct pt_regs *regs,
* contains valid data
*/
if (current->thread.used_vsr) {
- if (copy_ckvsx_to_user(&frame->mc_vsregs, current))
- return 1;
+ unsafe_copy_ckvsx_to_user(&frame->mc_vsregs, current, failed);
msr |= MSR_VSX;
}
#endif /* CONFIG_VSX */
@@ -415,91 +421,85 @@ static int save_tm_user_regs(struct pt_regs *regs,
* simply the same as in save_user_regs().
*/
if (current->thread.used_spe) {
- if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
- ELF_NEVRREG * sizeof(u32)))
- return 1;
+ unsafe_copy_to_user(&frame->mc_vregs, current->thread.evr,
+ ELF_NEVRREG * sizeof(u32), failed);
/* set MSR_SPE in the saved MSR value to indicate that
* frame->mc_vregs contains valid data */
msr |= MSR_SPE;
}
/* We always copy to/from spefscr */
- if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
- return 1;
+ unsafe_put_user(current->thread.spefscr,
+ (u32 __user *)&frame->mc_vregs + ELF_NEVRREG, failed);
#endif /* CONFIG_SPE */
- if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
- return 1;
+ unsafe_put_user(msr, &frame->mc_gregs[PT_MSR], failed);
+
if (sigret) {
/* Set up the sigreturn trampoline: li 0,sigret; sc */
- if (__put_user(PPC_INST_ADDI + sigret, &frame->tramp[0])
- || __put_user(PPC_INST_SC, &frame->tramp[1]))
- return 1;
+ unsafe_put_user(PPC_INST_ADDI + sigret, &frame->tramp[0], failed);
+ unsafe_put_user(PPC_INST_SC, &frame->tramp[1], failed);
}
+ user_write_access_end();
+
if (sigret)
flush_icache_range((unsigned long) &frame->tramp[0],
(unsigned long) &frame->tramp[2]);
- if (save_general_regs(regs, tm_frame))
+ if (!user_write_access_begin(tm_frame, sizeof(*tm_frame)))
return 1;
+ if (save_general_regs(regs, tm_frame))
+ goto failed;
+
/* Stash the top half of the 64bit MSR into the 32bit MSR word
* of the transactional mcontext. This way we have a backward-compatible
* MSR in the 'normal' (checkpointed) mcontext and additionally one can
* also look at what type of transaction (T or S) was active at the
* time of the signal.
*/
- if (__put_user((msr >> 32), &tm_frame->mc_gregs[PT_MSR]))
- return 1;
+ unsafe_put_user((msr >> 32), &tm_frame->mc_gregs[PT_MSR], failed);
#ifdef CONFIG_ALTIVEC
if (current->thread.used_vr) {
- if (msr & MSR_VEC) {
- if (__copy_to_user(&tm_frame->mc_vregs,
- ¤t->thread.vr_state,
- ELF_NVRREG * sizeof(vector128)))
- return 1;
- } else {
- if (__copy_to_user(&tm_frame->mc_vregs,
- ¤t->thread.ckvr_state,
- ELF_NVRREG * sizeof(vector128)))
- return 1;
- }
+ if (msr & MSR_VEC)
+ unsafe_copy_to_user(&tm_frame->mc_vregs,
+ ¤t->thread.vr_state,
+ ELF_NVRREG * sizeof(vector128), failed);
+ else
+ unsafe_copy_to_user(&tm_frame->mc_vregs,
+ ¤t->thread.ckvr_state,
+ ELF_NVRREG * sizeof(vector128), failed);
}
- if (msr & MSR_VEC) {
- if (__put_user(current->thread.vrsave,
- (u32 __user *)&tm_frame->mc_vregs[32]))
- return 1;
- } else {
- if (__put_user(current->thread.ckvrsave,
- (u32 __user *)&tm_frame->mc_vregs[32]))
- return 1;
- }
+ if (msr & MSR_VEC)
+ unsafe_put_user(current->thread.vrsave,
+ (u32 __user *)&tm_frame->mc_vregs[32], failed);
+ else
+ unsafe_put_user(current->thread.ckvrsave,
+ (u32 __user *)&tm_frame->mc_vregs[32], failed);
#endif /* CONFIG_ALTIVEC */
- if (msr & MSR_FP) {
- if (copy_fpr_to_user(&tm_frame->mc_fregs, current))
- return 1;
- } else {
- if (copy_ckfpr_to_user(&tm_frame->mc_fregs, current))
- return 1;
- }
+ if (msr & MSR_FP)
+ unsafe_copy_fpr_to_user(&tm_frame->mc_fregs, current, failed);
+ else
+ unsafe_copy_ckfpr_to_user(&tm_frame->mc_fregs, current, failed);
#ifdef CONFIG_VSX
if (current->thread.used_vsr) {
- if (msr & MSR_VSX) {
- if (copy_vsx_to_user(&tm_frame->mc_vsregs,
- current))
- return 1;
- } else {
- if (copy_ckvsx_to_user(&tm_frame->mc_vsregs, current))
- return 1;
- }
+ if (msr & MSR_VSX)
+ unsafe_copy_vsx_to_user(&tm_frame->mc_vsregs, current, failed);
+ else
+ unsafe_copy_ckvsx_to_user(&tm_frame->mc_vsregs, current, failed);
}
#endif /* CONFIG_VSX */
+ user_write_access_end();
return 0;
+
+failed:
+ user_write_access_end();
+ return 1;
}
#endif
--
2.25.0
^ permalink raw reply related
* [RFC PATCH v1 15/19] powerpc/signal32: Switch handle_signal32() to user_access_begin() logic
From: Christophe Leroy @ 2020-08-12 12:06 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, ldv,
viro
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597233555.git.christophe.leroy@csgroup.eu>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal_32.c | 19 +++++++++++--------
1 file changed, 11 insertions(+), 8 deletions(-)
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 0d076c2a9f6c..4ea83578ba9d 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -1241,23 +1241,23 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
/* Set up Signal Frame */
frame = get_sigframe(ksig, tsk, sizeof(*frame), 1);
- if (!access_ok(frame, sizeof(*frame)))
+ if (!user_write_access_begin(frame, sizeof(*frame)))
goto badframe;
sc = (struct sigcontext __user *) &frame->sctx;
#if _NSIG != 64
#error "Please adjust handle_signal()"
#endif
- if (__put_user(to_user_ptr(ksig->ka.sa.sa_handler), &sc->handler)
- || __put_user(oldset->sig[0], &sc->oldmask)
+ unsafe_put_user(to_user_ptr(ksig->ka.sa.sa_handler), &sc->handler, failed);
+ unsafe_put_user(oldset->sig[0], &sc->oldmask, failed);
#ifdef CONFIG_PPC64
- || __put_user((oldset->sig[0] >> 32), &sc->_unused[3])
+ unsafe_put_user((oldset->sig[0] >> 32), &sc->_unused[3], failed);
#else
- || __put_user(oldset->sig[1], &sc->_unused[3])
+ unsafe_put_user(oldset->sig[1], &sc->_unused[3], failed);
#endif
- || __put_user(to_user_ptr(&frame->mctx), &sc->regs)
- || __put_user(ksig->sig, &sc->signal))
- goto badframe;
+ unsafe_put_user(to_user_ptr(&frame->mctx), &sc->regs, failed);
+ unsafe_put_user(ksig->sig, &sc->signal, failed);
+ user_write_access_end();
if (vdso32_sigtramp && tsk->mm->context.vdso_base) {
sigret = 0;
@@ -1300,6 +1300,9 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
regs->msr &= ~MSR_LE;
return 0;
+failed:
+ user_write_access_end();
+
badframe:
signal_fault(tsk, regs, "handle_signal32", frame);
--
2.25.0
^ permalink raw reply related
* [RFC PATCH v1 11/19] powerpc/signal32: Simplify logging in handle_rt_signal32()
From: Christophe Leroy @ 2020-08-12 12:06 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, ldv,
viro
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597233555.git.christophe.leroy@csgroup.eu>
If something is bad in the frame, there is no point in
knowing which part of the frame exactly is wrong as it
got allocated as a single block.
Always print the root address of the frame in case on
failed user access, just like handle_signal32().
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal_32.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index d1087dd87174..495bee1b713d 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -754,7 +754,6 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
struct rt_sigframe __user *rt_sf;
struct mcontext __user *frame;
struct mcontext __user *tm_frame = NULL;
- void __user *addr;
unsigned long newsp = 0;
int sigret;
unsigned long tramp;
@@ -769,7 +768,6 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
/* Set up Signal Frame */
/* Put a Real Time Context onto stack */
rt_sf = get_sigframe(ksig, tsk, sizeof(*rt_sf), 1);
- addr = rt_sf;
if (!access_ok(rt_sf, sizeof(*rt_sf)))
goto badframe;
@@ -784,7 +782,6 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
/* Save user registers on the stack */
frame = &rt_sf->uc.uc_mcontext;
- addr = frame;
if (vdso32_rt_sigtramp && tsk->mm->context.vdso_base) {
sigret = 0;
tramp = tsk->mm->context.vdso_base + vdso32_rt_sigtramp;
@@ -820,7 +817,6 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
/* create a stack frame for the caller of the handler */
newsp = ((unsigned long)rt_sf) - (__SIGNAL_FRAMESIZE + 16);
- addr = (void __user *)regs->gpr[1];
if (put_user(regs->gpr[1], (u32 __user *)newsp))
goto badframe;
@@ -837,7 +833,7 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
return 0;
badframe:
- signal_fault(tsk, regs, "handle_rt_signal32", addr);
+ signal_fault(tsk, regs, "handle_rt_signal32", rt_sf);
return 1;
}
--
2.25.0
^ permalink raw reply related
* [RFC PATCH v1 16/19] powerpc/signal32: Switch handle_rt_signal32() to user_access_begin() logic
From: Christophe Leroy @ 2020-08-12 12:06 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, ldv,
viro
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597233555.git.christophe.leroy@csgroup.eu>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal_32.c | 47 +++++++++++++++++++++------------
1 file changed, 30 insertions(+), 17 deletions(-)
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 4ea83578ba9d..d03ba3d8eb68 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -58,8 +58,6 @@
#define mcontext mcontext32
#define ucontext ucontext32
-#define __save_altstack __compat_save_altstack
-
/*
* Userspace code may pass a ucontext which doesn't include VSX added
* at the end. We need to check for this case.
@@ -797,16 +795,36 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
/* Set up Signal Frame */
/* Put a Real Time Context onto stack */
rt_sf = get_sigframe(ksig, tsk, sizeof(*rt_sf), 1);
- if (!access_ok(rt_sf, sizeof(*rt_sf)))
+ if (!user_write_access_begin(rt_sf, sizeof(*rt_sf)))
goto badframe;
/* Put the siginfo & fill in most of the ucontext */
- if (copy_siginfo_to_user(&rt_sf->info, &ksig->info)
- || __put_user(0, &rt_sf->uc.uc_flags)
- || __save_altstack(&rt_sf->uc.uc_stack, regs->gpr[1])
- || __put_user(to_user_ptr(&rt_sf->uc.uc_mcontext),
- &rt_sf->uc.uc_regs)
- || put_sigset_t(&rt_sf->uc.uc_sigmask, oldset))
+ unsafe_put_user(0, &rt_sf->uc.uc_flags, failed);
+#ifdef CONFIG_PPC64
+ unsafe_compat_save_altstack(&rt_sf->uc.uc_stack, regs->gpr[1], failed);
+#else
+ unsafe_save_altstack(&rt_sf->uc.uc_stack, regs->gpr[1], failed);
+#endif
+ unsafe_put_user(to_user_ptr(&rt_sf->uc.uc_mcontext), &rt_sf->uc.uc_regs, failed);
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+ tm_frame = &rt_sf->uc_transact.uc_mcontext;
+ if (MSR_TM_ACTIVE(msr)) {
+ unsafe_put_user((unsigned long)&rt_sf->uc_transact,
+ &rt_sf->uc.uc_link, failed);
+ unsafe_put_user((unsigned long)tm_frame,
+ &rt_sf->uc_transact.uc_regs, failed);
+ }
+ else
+#endif
+ {
+ unsafe_put_user(0, &rt_sf->uc.uc_link, failed);
+ }
+ user_write_access_end();
+
+ if (put_sigset_t(&rt_sf->uc.uc_sigmask, oldset))
+ goto badframe;
+ if (copy_siginfo_to_user(&rt_sf->info, &ksig->info))
goto badframe;
/* Save user registers on the stack */
@@ -820,21 +838,13 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
}
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
- tm_frame = &rt_sf->uc_transact.uc_mcontext;
if (MSR_TM_ACTIVE(msr)) {
- if (__put_user((unsigned long)&rt_sf->uc_transact,
- &rt_sf->uc.uc_link) ||
- __put_user((unsigned long)tm_frame,
- &rt_sf->uc_transact.uc_regs))
- goto badframe;
if (save_tm_user_regs(regs, frame, tm_frame, sigret, msr))
goto badframe;
}
else
#endif
{
- if (__put_user(0, &rt_sf->uc.uc_link))
- goto badframe;
if (save_user_regs(regs, frame, tm_frame, sigret, 1))
goto badframe;
}
@@ -861,6 +871,9 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
regs->msr |= (MSR_KERNEL & MSR_LE);
return 0;
+failed:
+ user_write_access_end();
+
badframe:
signal_fault(tsk, regs, "handle_rt_signal32", rt_sf);
--
2.25.0
^ permalink raw reply related
* [RFC PATCH v1 17/19] signal: Add unsafe_put_compat_sigset()
From: Christophe Leroy @ 2020-08-12 12:06 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, ldv,
viro
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597233555.git.christophe.leroy@csgroup.eu>
Implement 'unsafe' version of put_compat_sigset()
For the bigendian, use unsafe_put_user() directly
to avoid intermediate copy through the stack.
For the littleendian, use a straight unsafe_copy_to_user().
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dmitry V. Levin <ldv@altlinux.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
---
include/linux/compat.h | 32 ++++++++++++++++++++++++++++++++
1 file changed, 32 insertions(+)
diff --git a/include/linux/compat.h b/include/linux/compat.h
index c4255d8a4a8a..bbe5f9658ed1 100644
--- a/include/linux/compat.h
+++ b/include/linux/compat.h
@@ -442,6 +442,38 @@ put_compat_sigset(compat_sigset_t __user *compat, const sigset_t *set,
#endif
}
+#ifdef CONFIG_CPU_BIG_ENDIAN
+#define unsafe_put_compat_sigset(compat, set, label) do { \
+ compat_sigset_t __user *__c = compat; \
+ const sigset_t *__s = set; \
+ \
+ switch (_NSIG_WORDS) { \
+ case 4: \
+ unsafe_put_user(__s->sig[3] >> 32, __c->sig[7], label); \
+ unsafe_put_user(__s->sig[3], __c->sig[6], label); \
+ fallthrough; \
+ case 3: \
+ unsafe_put_user(__s->sig[2] >> 32, __c->sig[5], label); \
+ unsafe_put_user(__s->sig[2], __c->sig[4], label); \
+ fallthrough; \
+ case 2: \
+ unsafe_put_user(__s->sig[1] >> 32, __c->sig[3], label); \
+ unsafe_put_user(__s->sig[1], __c->sig[2], label); \
+ fallthrough; \
+ case 1: \
+ unsafe_put_user(__s->sig[0] >> 32, __c->sig[1], label); \
+ unsafe_put_user(__s->sig[0], __c->sig[0], label); \
+ } \
+} while (0)
+#else
+#define unsafe_put_compat_sigset(compat, set, label) do { \
+ compat_sigset_t __user *__c = compat; \
+ const sigset_t *__s = set; \
+ \
+ unsafe_copy_to_user(__c, __s, sizeof(*__c), label); \
+} while (0)
+#endif
+
extern int compat_ptrace_request(struct task_struct *child,
compat_long_t request,
compat_ulong_t addr, compat_ulong_t data);
--
2.25.0
^ permalink raw reply related
* [RFC PATCH v1 19/19] powerpc/signal32: Switch swap_context() to user_access_begin() logic
From: Christophe Leroy @ 2020-08-12 12:06 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, ldv,
viro
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597233555.git.christophe.leroy@csgroup.eu>
As this was the last user of put_sigset_t(), remove it as well.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal_32.c | 24 ++++++++++--------------
1 file changed, 10 insertions(+), 14 deletions(-)
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 6cbff0293ff4..399d823782cf 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -82,11 +82,6 @@
* Functions for flipping sigsets (thanks to brain dead generic
* implementation that makes things simple for little endian only)
*/
-static inline int put_sigset_t(compat_sigset_t __user *uset, sigset_t *set)
-{
- return put_compat_sigset(uset, set, sizeof(*uset));
-}
-
#define unsafe_put_sigset_t unsafe_put_compat_sigset
static inline int get_sigset_t(sigset_t *set,
@@ -140,11 +135,6 @@ static inline int restore_general_regs(struct pt_regs *regs,
#define GP_REGS_SIZE min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
-static inline int put_sigset_t(sigset_t __user *uset, sigset_t *set)
-{
- return copy_to_user(uset, set, sizeof(*uset));
-}
-
#define unsafe_put_sigset_t(uset, set, label) do { \
sigset_t __user *__us = uset ; \
const sigset_t *__s = set; \
@@ -1012,11 +1002,13 @@ SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
*/
mctx = (struct mcontext __user *)
((unsigned long) &old_ctx->uc_mcontext & ~0xfUL);
- if (!access_ok(old_ctx, ctx_size)
- || save_user_regs(regs, mctx, NULL, 0, ctx_has_vsx_region)
- || put_sigset_t(&old_ctx->uc_sigmask, ¤t->blocked)
- || __put_user(to_user_ptr(mctx), &old_ctx->uc_regs))
+ if (save_user_regs(regs, mctx, NULL, 0, ctx_has_vsx_region))
+ return -EFAULT;
+ if (!user_write_access_begin(old_ctx, ctx_size))
return -EFAULT;
+ unsafe_put_sigset_t(&old_ctx->uc_sigmask, ¤t->blocked, failed);
+ unsafe_put_user(to_user_ptr(mctx), &old_ctx->uc_regs, failed);
+ user_write_access_end();
}
if (new_ctx == NULL)
return 0;
@@ -1040,6 +1032,10 @@ SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
set_thread_flag(TIF_RESTOREALL);
return 0;
+
+failed:
+ user_write_access_end();
+ return -EFAULT;
}
#ifdef CONFIG_PPC64
--
2.25.0
^ permalink raw reply related
page: next (older) | prev (newer) | latest
- recent:[subjects (threaded)|topics (new)|topics (active)]
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox