* Re: [PATCH v9 5/6] powerpc/mm/kasan: rename kasan_init_32.c to init_32.c
From: Christophe Leroy @ 2020-12-01 16:56 UTC (permalink / raw)
To: Daniel Axtens, linux-kernel, linux-mm, linuxppc-dev, kasan-dev,
christophe.leroy, aneesh.kumar, bsingharora
In-Reply-To: <20201201161632.1234753-6-dja@axtens.net>
Le 01/12/2020 à 17:16, Daniel Axtens a écrit :
> kasan is already implied by the directory name, we don't need to
> repeat it.
>
> Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr>
My new address is <christophe.leroy@csgroup.eu>
> Signed-off-by: Daniel Axtens <dja@axtens.net>
> ---
> arch/powerpc/mm/kasan/Makefile | 2 +-
> arch/powerpc/mm/kasan/{kasan_init_32.c => init_32.c} | 0
> 2 files changed, 1 insertion(+), 1 deletion(-)
> rename arch/powerpc/mm/kasan/{kasan_init_32.c => init_32.c} (100%)
>
> diff --git a/arch/powerpc/mm/kasan/Makefile b/arch/powerpc/mm/kasan/Makefile
> index bb1a5408b86b..42fb628a44fd 100644
> --- a/arch/powerpc/mm/kasan/Makefile
> +++ b/arch/powerpc/mm/kasan/Makefile
> @@ -2,6 +2,6 @@
>
> KASAN_SANITIZE := n
>
> -obj-$(CONFIG_PPC32) += kasan_init_32.o
> +obj-$(CONFIG_PPC32) += init_32.o
> obj-$(CONFIG_PPC_8xx) += 8xx.o
> obj-$(CONFIG_PPC_BOOK3S_32) += book3s_32.o
> diff --git a/arch/powerpc/mm/kasan/kasan_init_32.c b/arch/powerpc/mm/kasan/init_32.c
> similarity index 100%
> rename from arch/powerpc/mm/kasan/kasan_init_32.c
> rename to arch/powerpc/mm/kasan/init_32.c
>
^ permalink raw reply
* Re: [PATCH v9 4/6] kasan: Document support on 32-bit powerpc
From: Christophe Leroy @ 2020-12-01 16:56 UTC (permalink / raw)
To: Daniel Axtens, linux-kernel, linux-mm, linuxppc-dev, kasan-dev,
christophe.leroy, aneesh.kumar, bsingharora
In-Reply-To: <20201201161632.1234753-5-dja@axtens.net>
Le 01/12/2020 à 17:16, Daniel Axtens a écrit :
> KASAN is supported on 32-bit powerpc and the docs should reflect this.
>
> Document s390 support while we're at it.
>
> Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr>
> Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
My new address is <christophe.leroy@csgroup.eu>
> Signed-off-by: Daniel Axtens <dja@axtens.net>
> ---
> Documentation/dev-tools/kasan.rst | 7 +++++--
> Documentation/powerpc/kasan.txt | 12 ++++++++++++
> 2 files changed, 17 insertions(+), 2 deletions(-)
> create mode 100644 Documentation/powerpc/kasan.txt
>
> diff --git a/Documentation/dev-tools/kasan.rst b/Documentation/dev-tools/kasan.rst
> index 2b68addaadcd..eaf868094a8e 100644
> --- a/Documentation/dev-tools/kasan.rst
> +++ b/Documentation/dev-tools/kasan.rst
> @@ -19,7 +19,8 @@ out-of-bounds accesses for global variables is only supported since Clang 11.
> Tag-based KASAN is only supported in Clang.
>
> Currently generic KASAN is supported for the x86_64, arm64, xtensa, s390 and
> -riscv architectures, and tag-based KASAN is supported only for arm64.
> +riscv architectures. It is also supported on 32-bit powerpc kernels. Tag-based
> +KASAN is supported only on arm64.
>
> Usage
> -----
> @@ -255,7 +256,9 @@ CONFIG_KASAN_VMALLOC
> ~~~~~~~~~~~~~~~~~~~~
>
> With ``CONFIG_KASAN_VMALLOC``, KASAN can cover vmalloc space at the
> -cost of greater memory usage. Currently this is only supported on x86.
> +cost of greater memory usage. Currently this supported on x86, s390
> +and 32-bit powerpc. It is optional, except on 32-bit powerpc kernels
> +with module support, where it is required.
>
> This works by hooking into vmalloc and vmap, and dynamically
> allocating real shadow memory to back the mappings.
> diff --git a/Documentation/powerpc/kasan.txt b/Documentation/powerpc/kasan.txt
> new file mode 100644
> index 000000000000..26bb0e8bb18c
> --- /dev/null
> +++ b/Documentation/powerpc/kasan.txt
> @@ -0,0 +1,12 @@
> +KASAN is supported on powerpc on 32-bit only.
> +
> +32 bit support
> +==============
> +
> +KASAN is supported on both hash and nohash MMUs on 32-bit.
> +
> +The shadow area sits at the top of the kernel virtual memory space above the
> +fixmap area and occupies one eighth of the total kernel virtual memory space.
> +
> +Instrumentation of the vmalloc area is optional, unless built with modules,
> +in which case it is required.
>
^ permalink raw reply
* Re: [PATCH v9 3/6] kasan: define and use MAX_PTRS_PER_* for early shadow tables
From: Christophe Leroy @ 2020-12-01 16:54 UTC (permalink / raw)
To: Daniel Axtens, linux-kernel, linux-mm, linuxppc-dev, kasan-dev,
christophe.leroy, aneesh.kumar, bsingharora
In-Reply-To: <20201201161632.1234753-4-dja@axtens.net>
Le 01/12/2020 à 17:16, Daniel Axtens a écrit :
> powerpc has a variable number of PTRS_PER_*, set at runtime based
> on the MMU that the kernel is booted under.
>
> This means the PTRS_PER_* are no longer constants, and therefore
> breaks the build.
>
> Define default MAX_PTRS_PER_*s in the same style as MAX_PTRS_PER_P4D.
> As KASAN is the only user at the moment, just define them in the kasan
> header, and have them default to PTRS_PER_* unless overridden in arch
> code.
>
> Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr>
My neww address is : christophe.leroy@csgroup.eu
> Suggested-by: Balbir Singh <bsingharora@gmail.com>
> Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Same
> Reviewed-by: Balbir Singh <bsingharora@gmail.com>
> Signed-off-by: Daniel Axtens <dja@axtens.net>
> ---
> include/linux/kasan.h | 18 +++++++++++++++---
> mm/kasan/init.c | 6 +++---
> 2 files changed, 18 insertions(+), 6 deletions(-)
>
> diff --git a/include/linux/kasan.h b/include/linux/kasan.h
> index 3df66fdf6662..893d054aad6f 100644
> --- a/include/linux/kasan.h
> +++ b/include/linux/kasan.h
> @@ -24,10 +24,22 @@ struct kunit_kasan_expectation {
> static inline bool kasan_arch_is_ready(void) { return true; }
> #endif
>
> +#ifndef MAX_PTRS_PER_PTE
> +#define MAX_PTRS_PER_PTE PTRS_PER_PTE
> +#endif
> +
> +#ifndef MAX_PTRS_PER_PMD
> +#define MAX_PTRS_PER_PMD PTRS_PER_PMD
> +#endif
> +
> +#ifndef MAX_PTRS_PER_PUD
> +#define MAX_PTRS_PER_PUD PTRS_PER_PUD
> +#endif
> +
> extern unsigned char kasan_early_shadow_page[PAGE_SIZE];
> -extern pte_t kasan_early_shadow_pte[PTRS_PER_PTE];
> -extern pmd_t kasan_early_shadow_pmd[PTRS_PER_PMD];
> -extern pud_t kasan_early_shadow_pud[PTRS_PER_PUD];
> +extern pte_t kasan_early_shadow_pte[MAX_PTRS_PER_PTE];
> +extern pmd_t kasan_early_shadow_pmd[MAX_PTRS_PER_PMD];
> +extern pud_t kasan_early_shadow_pud[MAX_PTRS_PER_PUD];
> extern p4d_t kasan_early_shadow_p4d[MAX_PTRS_PER_P4D];
>
> int kasan_populate_early_shadow(const void *shadow_start,
> diff --git a/mm/kasan/init.c b/mm/kasan/init.c
> index fe6be0be1f76..42bca3d27db8 100644
> --- a/mm/kasan/init.c
> +++ b/mm/kasan/init.c
> @@ -46,7 +46,7 @@ static inline bool kasan_p4d_table(pgd_t pgd)
> }
> #endif
> #if CONFIG_PGTABLE_LEVELS > 3
> -pud_t kasan_early_shadow_pud[PTRS_PER_PUD] __page_aligned_bss;
> +pud_t kasan_early_shadow_pud[MAX_PTRS_PER_PUD] __page_aligned_bss;
> static inline bool kasan_pud_table(p4d_t p4d)
> {
> return p4d_page(p4d) == virt_to_page(lm_alias(kasan_early_shadow_pud));
> @@ -58,7 +58,7 @@ static inline bool kasan_pud_table(p4d_t p4d)
> }
> #endif
> #if CONFIG_PGTABLE_LEVELS > 2
> -pmd_t kasan_early_shadow_pmd[PTRS_PER_PMD] __page_aligned_bss;
> +pmd_t kasan_early_shadow_pmd[MAX_PTRS_PER_PMD] __page_aligned_bss;
> static inline bool kasan_pmd_table(pud_t pud)
> {
> return pud_page(pud) == virt_to_page(lm_alias(kasan_early_shadow_pmd));
> @@ -69,7 +69,7 @@ static inline bool kasan_pmd_table(pud_t pud)
> return false;
> }
> #endif
> -pte_t kasan_early_shadow_pte[PTRS_PER_PTE] __page_aligned_bss;
> +pte_t kasan_early_shadow_pte[MAX_PTRS_PER_PTE] __page_aligned_bss;
>
> static inline bool kasan_pte_table(pmd_t pmd)
> {
>
^ permalink raw reply
* Re: [PATCH v9 2/6] kasan: allow architectures to provide an outline readiness check
From: Christophe Leroy @ 2020-12-01 16:53 UTC (permalink / raw)
To: Daniel Axtens, linux-kernel, linux-mm, linuxppc-dev, kasan-dev,
christophe.leroy, aneesh.kumar, bsingharora
Cc: Aneesh Kumar K . V
In-Reply-To: <20201201161632.1234753-3-dja@axtens.net>
Le 01/12/2020 à 17:16, Daniel Axtens a écrit :
> Allow architectures to define a kasan_arch_is_ready() hook that bails
> out of any function that's about to touch the shadow unless the arch
> says that it is ready for the memory to be accessed. This is fairly
> uninvasive and should have a negligible performance penalty.
>
> This will only work in outline mode, so an arch must specify
> HAVE_ARCH_NO_KASAN_INLINE if it requires this.
>
> Cc: Balbir Singh <bsingharora@gmail.com>
> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Did I signed that off one day ? I can't remember.
Please update my email address, and maybe change it to a Suggested-by: ? I think the first
Signed-off-by: has to be the author of the patch.
> Signed-off-by: Daniel Axtens <dja@axtens.net>
>
> --
>
> I discuss the justfication for this later in the series. Also,
> both previous RFCs for ppc64 - by 2 different people - have
> needed this trick! See:
> - https://lore.kernel.org/patchwork/patch/592820/ # ppc64 hash series
> - https://patchwork.ozlabs.org/patch/795211/ # ppc radix series
> ---
> include/linux/kasan.h | 4 ++++
> mm/kasan/common.c | 10 ++++++++++
> mm/kasan/generic.c | 3 +++
> 3 files changed, 17 insertions(+)
>
> diff --git a/include/linux/kasan.h b/include/linux/kasan.h
> index 30d343b4a40a..3df66fdf6662 100644
> --- a/include/linux/kasan.h
> +++ b/include/linux/kasan.h
> @@ -20,6 +20,10 @@ struct kunit_kasan_expectation {
> bool report_found;
> };
>
> +#ifndef kasan_arch_is_ready
> +static inline bool kasan_arch_is_ready(void) { return true; }
> +#endif
> +
> extern unsigned char kasan_early_shadow_page[PAGE_SIZE];
> extern pte_t kasan_early_shadow_pte[PTRS_PER_PTE];
> extern pmd_t kasan_early_shadow_pmd[PTRS_PER_PMD];
> diff --git a/mm/kasan/common.c b/mm/kasan/common.c
> index 950fd372a07e..ba7744d3e319 100644
> --- a/mm/kasan/common.c
> +++ b/mm/kasan/common.c
> @@ -117,6 +117,9 @@ void kasan_poison_shadow(const void *address, size_t size, u8 value)
> {
> void *shadow_start, *shadow_end;
>
> + if (!kasan_arch_is_ready())
> + return;
> +
> /*
> * Perform shadow offset calculation based on untagged address, as
> * some of the callers (e.g. kasan_poison_object_data) pass tagged
> @@ -134,6 +137,9 @@ void kasan_unpoison_shadow(const void *address, size_t size)
> {
> u8 tag = get_tag(address);
>
> + if (!kasan_arch_is_ready())
> + return;
> +
> /*
> * Perform shadow offset calculation based on untagged address, as
> * some of the callers (e.g. kasan_unpoison_object_data) pass tagged
> @@ -406,6 +412,10 @@ static bool __kasan_slab_free(struct kmem_cache *cache, void *object,
> if (unlikely(cache->flags & SLAB_TYPESAFE_BY_RCU))
> return false;
>
> + /* We can't read the shadow byte if the arch isn't ready */
> + if (!kasan_arch_is_ready())
> + return false;
> +
> shadow_byte = READ_ONCE(*(s8 *)kasan_mem_to_shadow(object));
> if (shadow_invalid(tag, shadow_byte)) {
> kasan_report_invalid_free(tagged_object, ip);
> diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c
> index 248264b9cb76..e87404026b2b 100644
> --- a/mm/kasan/generic.c
> +++ b/mm/kasan/generic.c
> @@ -169,6 +169,9 @@ static __always_inline bool check_memory_region_inline(unsigned long addr,
> size_t size, bool write,
> unsigned long ret_ip)
> {
> + if (!kasan_arch_is_ready())
> + return true;
> +
> if (unlikely(size == 0))
> return true;
>
>
^ permalink raw reply
* Re: [PATCH v9 1/6] kasan: allow an architecture to disable inline instrumentation
From: Christophe Leroy @ 2020-12-01 16:49 UTC (permalink / raw)
To: Daniel Axtens, linux-kernel, linux-mm, linuxppc-dev, kasan-dev,
christophe.leroy, aneesh.kumar, bsingharora
In-Reply-To: <20201201161632.1234753-2-dja@axtens.net>
Le 01/12/2020 à 17:16, Daniel Axtens a écrit :
> For annoying architectural reasons, it's very difficult to support inline
> instrumentation on powerpc64.
>
> Add a Kconfig flag to allow an arch to disable inline. (It's a bit
> annoying to be 'backwards', but I'm not aware of any way to have
> an arch force a symbol to be 'n', rather than 'y'.)
>
> Signed-off-by: Daniel Axtens <dja@axtens.net>
> ---
> lib/Kconfig.kasan | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan
> index 542a9c18398e..31a0b28f6c2b 100644
> --- a/lib/Kconfig.kasan
> +++ b/lib/Kconfig.kasan
> @@ -9,6 +9,9 @@ config HAVE_ARCH_KASAN_SW_TAGS
> config HAVE_ARCH_KASAN_VMALLOC
> bool
>
> +config HAVE_ARCH_NO_KASAN_INLINE
Maybe a better name could be: ARCH_DISABLE_KASAN_INLINE
> + def_bool n
> +
> config CC_HAS_KASAN_GENERIC
> def_bool $(cc-option, -fsanitize=kernel-address)
>
> @@ -108,6 +111,7 @@ config KASAN_OUTLINE
>
> config KASAN_INLINE
> bool "Inline instrumentation"
> + depends on !HAVE_ARCH_NO_KASAN_INLINE
> help
> Compiler directly inserts code checking shadow memory before
> memory accesses. This is faster than outline (in some workloads
>
^ permalink raw reply
* [PATCH v9 6/6] powerpc: Book3S 64-bit outline-only KASAN support
From: Daniel Axtens @ 2020-12-01 16:16 UTC (permalink / raw)
To: linux-kernel, linux-mm, linuxppc-dev, kasan-dev, christophe.leroy,
aneesh.kumar, bsingharora
Cc: Daniel Axtens
In-Reply-To: <20201201161632.1234753-1-dja@axtens.net>
Implement a limited form of KASAN for Book3S 64-bit machines running under
the Radix MMU, supporting only outline mode.
- Enable the compiler instrumentation to check addresses and maintain the
shadow region. (This is the guts of KASAN which we can easily reuse.)
- Require kasan-vmalloc support to handle modules and anything else in
vmalloc space.
- KASAN needs to be able to validate all pointer accesses, but we can't
instrument all kernel addresses - only linear map and vmalloc. On boot,
set up a single page of read-only shadow that marks all iomap and
vmemmap accesses as valid.
- Make our stack-walking code KASAN-safe by using READ_ONCE_NOCHECK -
generic code, arm64, s390 and x86 all do this for similar sorts of
reasons: when unwinding a stack, we might touch memory that KASAN has
marked as being out-of-bounds. In our case we often get this when
checking for an exception frame because we're checking an arbitrary
offset into the stack frame.
See commit 20955746320e ("s390/kasan: avoid false positives during stack
unwind"), commit bcaf669b4bdb ("arm64: disable kasan when accessing
frame->fp in unwind_frame"), commit 91e08ab0c851 ("x86/dumpstack:
Prevent KASAN false positive warnings") and commit 6e22c8366416
("tracing, kasan: Silence Kasan warning in check_stack of stack_tracer")
- Document KASAN in both generic and powerpc docs.
Background
----------
KASAN support on Book3S is a bit tricky to get right:
- It would be good to support inline instrumentation so as to be able to
catch stack issues that cannot be caught with outline mode.
- Inline instrumentation requires a fixed offset.
- Book3S runs code with translations off ("real mode") during boot,
including a lot of generic device-tree parsing code which is used to
determine MMU features.
[ppc64 mm note: The kernel installs a linear mapping at effective
address c000...-c008.... This is a one-to-one mapping with physical
memory from 0000... onward. Because of how memory accesses work on
powerpc 64-bit Book3S, a kernel pointer in the linear map accesses the
same memory both with translations on (accessing as an 'effective
address'), and with translations off (accessing as a 'real
address'). This works in both guests and the hypervisor. For more
details, see s5.7 of Book III of version 3 of the ISA, in particular
the Storage Control Overview, s5.7.3, and s5.7.5 - noting that this
KASAN implementation currently only supports Radix.]
- Some code - most notably a lot of KVM code - also runs with translations
off after boot.
- Therefore any offset has to point to memory that is valid with
translations on or off.
One approach is just to give up on inline instrumentation. This way
boot-time checks can be delayed until after the MMU is set is up, and we
can just not instrument any code that runs with translations off after
booting. Take this approach for now and require outline instrumentation.
Previous attempts allowed inline instrumentation. However, they came with
some unfortunate restrictions: only physically contiguous memory could be
used and it had to be specified at compile time. Maybe we can do better in
the future.
Cc: Balbir Singh <bsingharora@gmail.com> # ppc64 out-of-line radix version
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> # ppc64 hash version
Cc: Christophe Leroy <christophe.leroy@c-s.fr> # ppc32 version
Signed-off-by: Daniel Axtens <dja@axtens.net>
---
Documentation/dev-tools/kasan.rst | 9 +-
Documentation/powerpc/kasan.txt | 48 +++++++++-
arch/powerpc/Kconfig | 4 +-
arch/powerpc/Kconfig.debug | 2 +-
arch/powerpc/include/asm/book3s/64/hash.h | 4 +
arch/powerpc/include/asm/book3s/64/pgtable.h | 7 ++
arch/powerpc/include/asm/book3s/64/radix.h | 13 ++-
arch/powerpc/include/asm/kasan.h | 34 ++++++-
arch/powerpc/kernel/Makefile | 5 +
arch/powerpc/kernel/process.c | 16 ++--
arch/powerpc/kvm/Makefile | 5 +
arch/powerpc/mm/book3s64/Makefile | 8 ++
arch/powerpc/mm/kasan/Makefile | 1 +
arch/powerpc/mm/kasan/init_book3s_64.c | 98 ++++++++++++++++++++
arch/powerpc/mm/ptdump/ptdump.c | 20 +++-
arch/powerpc/platforms/Kconfig.cputype | 1 +
arch/powerpc/platforms/powernv/Makefile | 6 ++
arch/powerpc/platforms/pseries/Makefile | 3 +
18 files changed, 265 insertions(+), 19 deletions(-)
create mode 100644 arch/powerpc/mm/kasan/init_book3s_64.c
diff --git a/Documentation/dev-tools/kasan.rst b/Documentation/dev-tools/kasan.rst
index eaf868094a8e..28f08959bd2e 100644
--- a/Documentation/dev-tools/kasan.rst
+++ b/Documentation/dev-tools/kasan.rst
@@ -19,8 +19,9 @@ out-of-bounds accesses for global variables is only supported since Clang 11.
Tag-based KASAN is only supported in Clang.
Currently generic KASAN is supported for the x86_64, arm64, xtensa, s390 and
-riscv architectures. It is also supported on 32-bit powerpc kernels. Tag-based
-KASAN is supported only on arm64.
+riscv architectures. It is also supported on powerpc, for 32-bit kernels, and
+for 64-bit kernels running under the Radix MMU. Tag-based KASAN is supported
+only on arm64.
Usage
-----
@@ -257,8 +258,8 @@ CONFIG_KASAN_VMALLOC
With ``CONFIG_KASAN_VMALLOC``, KASAN can cover vmalloc space at the
cost of greater memory usage. Currently this supported on x86, s390
-and 32-bit powerpc. It is optional, except on 32-bit powerpc kernels
-with module support, where it is required.
+and powerpc. It is optional, except on 64-bit powerpc kernels, and on
+32-bit powerpc kernels with module support, where it is required.
This works by hooking into vmalloc and vmap, and dynamically
allocating real shadow memory to back the mappings.
diff --git a/Documentation/powerpc/kasan.txt b/Documentation/powerpc/kasan.txt
index 26bb0e8bb18c..f032b4eaf205 100644
--- a/Documentation/powerpc/kasan.txt
+++ b/Documentation/powerpc/kasan.txt
@@ -1,4 +1,4 @@
-KASAN is supported on powerpc on 32-bit only.
+KASAN is supported on powerpc on 32-bit and Radix 64-bit only.
32 bit support
==============
@@ -10,3 +10,49 @@ fixmap area and occupies one eighth of the total kernel virtual memory space.
Instrumentation of the vmalloc area is optional, unless built with modules,
in which case it is required.
+
+64 bit support
+==============
+
+Currently, only the radix MMU is supported. There have been versions for hash
+and Book3E processors floating around on the mailing list, but nothing has been
+merged.
+
+KASAN support on Book3S is a bit tricky to get right:
+
+ - It would be good to support inline instrumentation so as to be able to catch
+ stack issues that cannot be caught with outline mode.
+
+ - Inline instrumentation requires a fixed offset.
+
+ - Book3S runs code with translations off ("real mode") during boot, including a
+ lot of generic device-tree parsing code which is used to determine MMU
+ features.
+
+ - Some code - most notably a lot of KVM code - also runs with translations off
+ after boot.
+
+ - Therefore any offset has to point to memory that is valid with
+ translations on or off.
+
+One approach is just to give up on inline instrumentation. This way boot-time
+checks can be delayed until after the MMU is set is up, and we can just not
+instrument any code that runs with translations off after booting. This is the
+current approach.
+
+To avoid this limitiation, the KASAN shadow would have to be placed inside the
+linear mapping, using the same high-bits trick we use for the rest of the linear
+mapping. This is tricky:
+
+ - We'd like to place it near the start of physical memory. In theory we can do
+ this at run-time based on how much physical memory we have, but this requires
+ being able to arbitrarily relocate the kernel, which is basically the tricky
+ part of KASLR. Not being game to implement both tricky things at once, this
+ is hopefully something we can revisit once we get KASLR for Book3S.
+
+ - Alternatively, we can place the shadow at the _end_ of memory, but this
+ requires knowing how much contiguous physical memory a system has _at compile
+ time_. This is a big hammer, and has some unfortunate consequences: inablity
+ to handle discontiguous physical memory, total failure to boot on machines
+ with less memory than specified, and that machines with more memory than
+ specified can't use it. This was deemed unacceptable.
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index e9f13fe08492..e6bd02af6ebd 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -180,7 +180,9 @@ config PPC
select HAVE_ARCH_HUGE_VMAP if PPC_BOOK3S_64 && PPC_RADIX_MMU
select HAVE_ARCH_JUMP_LABEL
select HAVE_ARCH_KASAN if PPC32 && PPC_PAGE_SHIFT <= 14
- select HAVE_ARCH_KASAN_VMALLOC if PPC32 && PPC_PAGE_SHIFT <= 14
+ select HAVE_ARCH_KASAN if PPC_BOOK3S_64 && PPC_RADIX_MMU
+ select HAVE_ARCH_NO_KASAN_INLINE if PPC_BOOK3S_64 && PPC_RADIX_MMU
+ select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN
select HAVE_ARCH_KGDB
select HAVE_ARCH_MMAP_RND_BITS
select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
diff --git a/arch/powerpc/Kconfig.debug b/arch/powerpc/Kconfig.debug
index b88900f4832f..60c1bba72a6f 100644
--- a/arch/powerpc/Kconfig.debug
+++ b/arch/powerpc/Kconfig.debug
@@ -396,5 +396,5 @@ config PPC_FAST_ENDIAN_SWITCH
config KASAN_SHADOW_OFFSET
hex
- depends on KASAN
+ depends on KASAN && PPC32
default 0xe0000000
diff --git a/arch/powerpc/include/asm/book3s/64/hash.h b/arch/powerpc/include/asm/book3s/64/hash.h
index 73ad038ed10b..105b90594a8a 100644
--- a/arch/powerpc/include/asm/book3s/64/hash.h
+++ b/arch/powerpc/include/asm/book3s/64/hash.h
@@ -18,6 +18,10 @@
#include <asm/book3s/64/hash-4k.h>
#endif
+#define H_PTRS_PER_PTE (1 << H_PTE_INDEX_SIZE)
+#define H_PTRS_PER_PMD (1 << H_PMD_INDEX_SIZE)
+#define H_PTRS_PER_PUD (1 << H_PUD_INDEX_SIZE)
+
/* Bits to set in a PMD/PUD/PGD entry valid bit*/
#define HASH_PMD_VAL_BITS (0x8000000000000000UL)
#define HASH_PUD_VAL_BITS (0x8000000000000000UL)
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
index a39886681629..767e239d75e3 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -230,6 +230,13 @@ extern unsigned long __pmd_frag_size_shift;
#define PTRS_PER_PUD (1 << PUD_INDEX_SIZE)
#define PTRS_PER_PGD (1 << PGD_INDEX_SIZE)
+#define MAX_PTRS_PER_PTE ((H_PTRS_PER_PTE > R_PTRS_PER_PTE) ? \
+ H_PTRS_PER_PTE : R_PTRS_PER_PTE)
+#define MAX_PTRS_PER_PMD ((H_PTRS_PER_PMD > R_PTRS_PER_PMD) ? \
+ H_PTRS_PER_PMD : R_PTRS_PER_PMD)
+#define MAX_PTRS_PER_PUD ((H_PTRS_PER_PUD > R_PTRS_PER_PUD) ? \
+ H_PTRS_PER_PUD : R_PTRS_PER_PUD)
+
/* PMD_SHIFT determines what a second-level page table entry can map */
#define PMD_SHIFT (PAGE_SHIFT + PTE_INDEX_SIZE)
#define PMD_SIZE (1UL << PMD_SHIFT)
diff --git a/arch/powerpc/include/asm/book3s/64/radix.h b/arch/powerpc/include/asm/book3s/64/radix.h
index c7813dc628fc..b3492b80f858 100644
--- a/arch/powerpc/include/asm/book3s/64/radix.h
+++ b/arch/powerpc/include/asm/book3s/64/radix.h
@@ -35,6 +35,11 @@
#define RADIX_PMD_SHIFT (PAGE_SHIFT + RADIX_PTE_INDEX_SIZE)
#define RADIX_PUD_SHIFT (RADIX_PMD_SHIFT + RADIX_PMD_INDEX_SIZE)
#define RADIX_PGD_SHIFT (RADIX_PUD_SHIFT + RADIX_PUD_INDEX_SIZE)
+
+#define R_PTRS_PER_PTE (1 << RADIX_PTE_INDEX_SIZE)
+#define R_PTRS_PER_PMD (1 << RADIX_PMD_INDEX_SIZE)
+#define R_PTRS_PER_PUD (1 << RADIX_PUD_INDEX_SIZE)
+
/*
* Size of EA range mapped by our pagetables.
*/
@@ -68,11 +73,11 @@
*
*
* 3rd quadrant expanded:
- * +------------------------------+
+ * +------------------------------+ Highest address (0xc010000000000000)
+ * +------------------------------+ KASAN shadow end (0xc00fc00000000000)
* | |
* | |
- * | |
- * +------------------------------+ Kernel vmemmap end (0xc010000000000000)
+ * +------------------------------+ Kernel vmemmap end/shadow start (0xc00e000000000000)
* | |
* | 512TB |
* | |
@@ -126,6 +131,8 @@
#define RADIX_VMEMMAP_SIZE RADIX_KERN_MAP_SIZE
#define RADIX_VMEMMAP_END (RADIX_VMEMMAP_START + RADIX_VMEMMAP_SIZE)
+/* For the sizes of the shadow area, see kasan.h */
+
#ifndef __ASSEMBLY__
#define RADIX_PTE_TABLE_SIZE (sizeof(pte_t) << RADIX_PTE_INDEX_SIZE)
#define RADIX_PMD_TABLE_SIZE (sizeof(pmd_t) << RADIX_PMD_INDEX_SIZE)
diff --git a/arch/powerpc/include/asm/kasan.h b/arch/powerpc/include/asm/kasan.h
index 7355ed05e65e..c72fd9281b44 100644
--- a/arch/powerpc/include/asm/kasan.h
+++ b/arch/powerpc/include/asm/kasan.h
@@ -28,9 +28,41 @@
#define KASAN_SHADOW_START (KASAN_SHADOW_OFFSET + \
(KASAN_KERN_START >> KASAN_SHADOW_SCALE_SHIFT))
+#ifdef CONFIG_KASAN_SHADOW_OFFSET
#define KASAN_SHADOW_OFFSET ASM_CONST(CONFIG_KASAN_SHADOW_OFFSET)
+#endif
+#ifdef CONFIG_PPC32
#define KASAN_SHADOW_END (-(-KASAN_SHADOW_START >> KASAN_SHADOW_SCALE_SHIFT))
+#endif
+
+#ifdef CONFIG_PPC_BOOK3S_64
+/*
+ * We define the offset such that the shadow of the linear map lives
+ * at the end of vmemmap space, that is, we choose offset such that
+ * shadow(c000_0000_0000_0000) = c00e_0000_0000_0000. This gives:
+ * c00e000000000000 - c000000000000000 >> 3 = a80e000000000000
+ */
+#define KASAN_SHADOW_OFFSET ASM_CONST(0xa80e000000000000)
+
+/*
+ * The shadow ends before the highest accessible address
+ * because we don't need a shadow for the shadow. Instead:
+ * c00e000000000000 << 3 + a80e000000000000000 = c00fc00000000000
+ */
+#define KASAN_SHADOW_END 0xc00fc00000000000UL
+
+DECLARE_STATIC_KEY_FALSE(powerpc_kasan_enabled_key);
+
+static inline bool kasan_arch_is_ready_ppc64(void)
+{
+ if (static_branch_likely(&powerpc_kasan_enabled_key))
+ return true;
+ return false;
+}
+
+#define kasan_arch_is_ready kasan_arch_is_ready_ppc64
+#endif
#ifdef CONFIG_KASAN
void kasan_early_init(void);
@@ -47,5 +79,5 @@ void kasan_update_early_region(unsigned long k_start, unsigned long k_end, pte_t
int kasan_init_shadow_page_tables(unsigned long k_start, unsigned long k_end);
int kasan_init_region(void *start, size_t size);
-#endif /* __ASSEMBLY */
+#endif /* !__ASSEMBLY__ */
#endif
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index fe2ef598e2ea..cd58202459dd 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -32,6 +32,11 @@ KASAN_SANITIZE_early_32.o := n
KASAN_SANITIZE_cputable.o := n
KASAN_SANITIZE_prom_init.o := n
KASAN_SANITIZE_btext.o := n
+KASAN_SANITIZE_paca.o := n
+KASAN_SANITIZE_setup_64.o := n
+KASAN_SANITIZE_mce.o := n
+KASAN_SANITIZE_traps.o := n
+KASAN_SANITIZE_mce_power.o := n
ifdef CONFIG_KASAN
CFLAGS_early_32.o += -DDISABLE_BRANCH_PROFILING
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index d421a2c7f822..f02b2766015c 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -2151,8 +2151,8 @@ void show_stack(struct task_struct *tsk, unsigned long *stack,
break;
stack = (unsigned long *) sp;
- newsp = stack[0];
- ip = stack[STACK_FRAME_LR_SAVE];
+ newsp = READ_ONCE_NOCHECK(stack[0]);
+ ip = READ_ONCE_NOCHECK(stack[STACK_FRAME_LR_SAVE]);
if (!firstframe || ip != lr) {
printk("%s["REG"] ["REG"] %pS",
loglvl, sp, ip, (void *)ip);
@@ -2170,14 +2170,16 @@ void show_stack(struct task_struct *tsk, unsigned long *stack,
* See if this is an exception frame.
* We look for the "regshere" marker in the current frame.
*/
- if (validate_sp(sp, tsk, STACK_INT_FRAME_SIZE)
- && stack[STACK_FRAME_MARKER] == STACK_FRAME_REGS_MARKER) {
+ if (validate_sp(sp, tsk, STACK_INT_FRAME_SIZE) &&
+ (READ_ONCE_NOCHECK(stack[STACK_FRAME_MARKER]) ==
+ STACK_FRAME_REGS_MARKER)) {
struct pt_regs *regs = (struct pt_regs *)
(sp + STACK_FRAME_OVERHEAD);
- lr = regs->link;
+ lr = READ_ONCE_NOCHECK(regs->link);
printk("%s--- interrupt: %lx at %pS\n LR = %pS\n",
- loglvl, regs->trap,
- (void *)regs->nip, (void *)lr);
+ loglvl, READ_ONCE_NOCHECK(regs->trap),
+ (void *)READ_ONCE_NOCHECK(regs->nip),
+ (void *)READ_ONCE_NOCHECK(lr));
firstframe = 1;
}
diff --git a/arch/powerpc/kvm/Makefile b/arch/powerpc/kvm/Makefile
index 2bfeaa13befb..7f1592dacbeb 100644
--- a/arch/powerpc/kvm/Makefile
+++ b/arch/powerpc/kvm/Makefile
@@ -136,3 +136,8 @@ obj-$(CONFIG_KVM_BOOK3S_64_PR) += kvm-pr.o
obj-$(CONFIG_KVM_BOOK3S_64_HV) += kvm-hv.o
obj-y += $(kvm-book3s_64-builtin-objs-y)
+
+# KVM does a lot in real-mode, and 64-bit Book3S KASAN doesn't support that
+ifdef CONFIG_PPC_BOOK3S_64
+KASAN_SANITIZE := n
+endif
diff --git a/arch/powerpc/mm/book3s64/Makefile b/arch/powerpc/mm/book3s64/Makefile
index fd393b8be14f..41a86d2c7da4 100644
--- a/arch/powerpc/mm/book3s64/Makefile
+++ b/arch/powerpc/mm/book3s64/Makefile
@@ -21,3 +21,11 @@ obj-$(CONFIG_PPC_MEM_KEYS) += pkeys.o
# Instrumenting the SLB fault path can lead to duplicate SLB entries
KCOV_INSTRUMENT_slb.o := n
+
+# Parts of these can run in real mode and therefore are
+# not safe with the current outline KASAN implementation
+KASAN_SANITIZE_mmu_context.o := n
+KASAN_SANITIZE_pgtable.o := n
+KASAN_SANITIZE_radix_pgtable.o := n
+KASAN_SANITIZE_radix_tlb.o := n
+KASAN_SANITIZE_slb.o := n
diff --git a/arch/powerpc/mm/kasan/Makefile b/arch/powerpc/mm/kasan/Makefile
index 42fb628a44fd..07eef87abd6c 100644
--- a/arch/powerpc/mm/kasan/Makefile
+++ b/arch/powerpc/mm/kasan/Makefile
@@ -5,3 +5,4 @@ KASAN_SANITIZE := n
obj-$(CONFIG_PPC32) += init_32.o
obj-$(CONFIG_PPC_8xx) += 8xx.o
obj-$(CONFIG_PPC_BOOK3S_32) += book3s_32.o
+obj-$(CONFIG_PPC_BOOK3S_64) += init_book3s_64.o
diff --git a/arch/powerpc/mm/kasan/init_book3s_64.c b/arch/powerpc/mm/kasan/init_book3s_64.c
new file mode 100644
index 000000000000..b26ada73215d
--- /dev/null
+++ b/arch/powerpc/mm/kasan/init_book3s_64.c
@@ -0,0 +1,98 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KASAN for 64-bit Book3S powerpc
+ *
+ * Copyright (C) 2019-2020 IBM Corporation
+ * Author: Daniel Axtens <dja@axtens.net>
+ */
+
+#define DISABLE_BRANCH_PROFILING
+
+#include <linux/kasan.h>
+#include <linux/printk.h>
+#include <linux/sched/task.h>
+#include <linux/memblock.h>
+#include <asm/pgalloc.h>
+
+DEFINE_STATIC_KEY_FALSE(powerpc_kasan_enabled_key);
+
+static void __init kasan_init_phys_region(void *start, void *end)
+{
+ unsigned long k_start, k_end, k_cur;
+ void *va;
+
+ if (start >= end)
+ return;
+
+ k_start = ALIGN_DOWN((unsigned long)kasan_mem_to_shadow(start), PAGE_SIZE);
+ k_end = ALIGN((unsigned long)kasan_mem_to_shadow(end), PAGE_SIZE);
+
+ va = memblock_alloc(k_end - k_start, PAGE_SIZE);
+ for (k_cur = k_start; k_cur < k_end; k_cur += PAGE_SIZE) {
+ map_kernel_page(k_cur, __pa(va), PAGE_KERNEL);
+ va += PAGE_SIZE;
+ }
+}
+
+void __init kasan_init(void)
+{
+ /*
+ * We want to do the following things:
+ * 1) Map real memory into the shadow for all physical memblocks
+ * This takes us from c000... to c008...
+ * 2) Leave a hole over the shadow of vmalloc space. KASAN_VMALLOC
+ * will manage this for us.
+ * This takes us from c008... to c00a...
+ * 3) Map the 'early shadow'/zero page over iomap and vmemmap space.
+ * This takes us up to where we start at c00e...
+ */
+
+ void *k_start = kasan_mem_to_shadow((void *)RADIX_VMALLOC_END);
+ void *k_end = kasan_mem_to_shadow((void *)RADIX_VMEMMAP_END);
+ phys_addr_t start, end;
+ u64 i;
+ pte_t zero_pte = pfn_pte(virt_to_pfn(kasan_early_shadow_page), PAGE_KERNEL);
+
+ if (!early_radix_enabled())
+ panic("KASAN requires radix!");
+
+ for_each_mem_range(i, &start, &end) {
+ kasan_init_phys_region((void *)start, (void *)end);
+ }
+
+ for (i = 0; i < PTRS_PER_PTE; i++)
+ __set_pte_at(&init_mm, (unsigned long)kasan_early_shadow_page,
+ &kasan_early_shadow_pte[i], zero_pte, 0);
+
+ for (i = 0; i < PTRS_PER_PMD; i++)
+ pmd_populate_kernel(&init_mm, &kasan_early_shadow_pmd[i],
+ kasan_early_shadow_pte);
+
+ for (i = 0; i < PTRS_PER_PUD; i++)
+ pud_populate(&init_mm, &kasan_early_shadow_pud[i],
+ kasan_early_shadow_pmd);
+
+ /* map the early shadow over the iomap and vmemmap space */
+ kasan_populate_early_shadow(k_start, k_end);
+
+ /* mark early shadow region as RO and wipe it */
+ zero_pte = pfn_pte(virt_to_pfn(kasan_early_shadow_page), PAGE_KERNEL_RO);
+ for (i = 0; i < PTRS_PER_PTE; i++)
+ __set_pte_at(&init_mm, (unsigned long)kasan_early_shadow_page,
+ &kasan_early_shadow_pte[i], zero_pte, 0);
+
+ /*
+ * clear_page relies on some cache info that hasn't been set up yet.
+ * It ends up looping ~forever and blows up other data.
+ * Use memset instead.
+ */
+ memset(kasan_early_shadow_page, 0, PAGE_SIZE);
+
+ static_branch_inc(&powerpc_kasan_enabled_key);
+
+ /* Enable error messages */
+ init_task.kasan_depth = 0;
+ pr_info("KASAN init done (64-bit Book3S)\n");
+}
+
+void __init kasan_late_init(void) { }
diff --git a/arch/powerpc/mm/ptdump/ptdump.c b/arch/powerpc/mm/ptdump/ptdump.c
index aca354fb670b..63672aa656e8 100644
--- a/arch/powerpc/mm/ptdump/ptdump.c
+++ b/arch/powerpc/mm/ptdump/ptdump.c
@@ -20,6 +20,7 @@
#include <linux/seq_file.h>
#include <asm/fixmap.h>
#include <linux/const.h>
+#include <linux/kasan.h>
#include <asm/page.h>
#include <asm/hugetlb.h>
@@ -317,6 +318,23 @@ static void walk_pud(struct pg_state *st, p4d_t *p4d, unsigned long start)
unsigned long addr;
unsigned int i;
+#if defined(CONFIG_KASAN) && defined(CONFIG_PPC_BOOK3S_64)
+ /*
+ * On radix + KASAN, we want to check for the KASAN "early" shadow
+ * which covers huge quantities of memory with the same set of
+ * read-only PTEs. If it is, we want to note the first page (to see
+ * the status change), and then note the last page. This gives us good
+ * results without spending ages noting the exact same PTEs over 100s of
+ * terabytes of memory.
+ */
+ if (p4d_page(*p4d) == virt_to_page(lm_alias(kasan_early_shadow_pud))) {
+ walk_pmd(st, pud, start);
+ addr = start + (PTRS_PER_PUD - 1) * PUD_SIZE;
+ walk_pmd(st, pud, addr);
+ return;
+ }
+#endif
+
for (i = 0; i < PTRS_PER_PUD; i++, pud++) {
addr = start + i * PUD_SIZE;
if (!pud_none(*pud) && !pud_is_leaf(*pud))
@@ -387,11 +405,11 @@ static void populate_markers(void)
#endif
address_markers[i++].start_address = FIXADDR_START;
address_markers[i++].start_address = FIXADDR_TOP;
+#endif /* CONFIG_PPC64 */
#ifdef CONFIG_KASAN
address_markers[i++].start_address = KASAN_SHADOW_START;
address_markers[i++].start_address = KASAN_SHADOW_END;
#endif
-#endif /* CONFIG_PPC64 */
}
static int ptdump_show(struct seq_file *m, void *v)
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index c194c4ae8bc7..b6eb8ec1e5ad 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -92,6 +92,7 @@ config PPC_BOOK3S_64
select ARCH_SUPPORTS_NUMA_BALANCING
select IRQ_WORK
select PPC_MM_SLICES
+ select KASAN_VMALLOC if KASAN
config PPC_BOOK3E_64
bool "Embedded processors"
diff --git a/arch/powerpc/platforms/powernv/Makefile b/arch/powerpc/platforms/powernv/Makefile
index 2eb6ae150d1f..f277e4793696 100644
--- a/arch/powerpc/platforms/powernv/Makefile
+++ b/arch/powerpc/platforms/powernv/Makefile
@@ -1,4 +1,10 @@
# SPDX-License-Identifier: GPL-2.0
+
+# nothing that deals with real mode is safe to KASAN
+# in particular, idle code runs a bunch of things in real mode
+KASAN_SANITIZE_idle.o := n
+KASAN_SANITIZE_pci-ioda.o := n
+
obj-y += setup.o opal-call.o opal-wrappers.o opal.o opal-async.o
obj-y += idle.o opal-rtc.o opal-nvram.o opal-lpc.o opal-flash.o
obj-y += rng.o opal-elog.o opal-dump.o opal-sysparam.o opal-sensor.o
diff --git a/arch/powerpc/platforms/pseries/Makefile b/arch/powerpc/platforms/pseries/Makefile
index c8a2b0b05ac0..202199ef9e5c 100644
--- a/arch/powerpc/platforms/pseries/Makefile
+++ b/arch/powerpc/platforms/pseries/Makefile
@@ -30,3 +30,6 @@ obj-$(CONFIG_PPC_SVM) += svm.o
obj-$(CONFIG_FA_DUMP) += rtas-fadump.o
obj-$(CONFIG_SUSPEND) += suspend.o
+
+# nothing that operates in real mode is safe for KASAN
+KASAN_SANITIZE_ras.o := n
--
2.25.1
^ permalink raw reply related
* [PATCH v9 5/6] powerpc/mm/kasan: rename kasan_init_32.c to init_32.c
From: Daniel Axtens @ 2020-12-01 16:16 UTC (permalink / raw)
To: linux-kernel, linux-mm, linuxppc-dev, kasan-dev, christophe.leroy,
aneesh.kumar, bsingharora
Cc: Daniel Axtens
In-Reply-To: <20201201161632.1234753-1-dja@axtens.net>
kasan is already implied by the directory name, we don't need to
repeat it.
Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Daniel Axtens <dja@axtens.net>
---
arch/powerpc/mm/kasan/Makefile | 2 +-
arch/powerpc/mm/kasan/{kasan_init_32.c => init_32.c} | 0
2 files changed, 1 insertion(+), 1 deletion(-)
rename arch/powerpc/mm/kasan/{kasan_init_32.c => init_32.c} (100%)
diff --git a/arch/powerpc/mm/kasan/Makefile b/arch/powerpc/mm/kasan/Makefile
index bb1a5408b86b..42fb628a44fd 100644
--- a/arch/powerpc/mm/kasan/Makefile
+++ b/arch/powerpc/mm/kasan/Makefile
@@ -2,6 +2,6 @@
KASAN_SANITIZE := n
-obj-$(CONFIG_PPC32) += kasan_init_32.o
+obj-$(CONFIG_PPC32) += init_32.o
obj-$(CONFIG_PPC_8xx) += 8xx.o
obj-$(CONFIG_PPC_BOOK3S_32) += book3s_32.o
diff --git a/arch/powerpc/mm/kasan/kasan_init_32.c b/arch/powerpc/mm/kasan/init_32.c
similarity index 100%
rename from arch/powerpc/mm/kasan/kasan_init_32.c
rename to arch/powerpc/mm/kasan/init_32.c
--
2.25.1
^ permalink raw reply related
* [PATCH v9 4/6] kasan: Document support on 32-bit powerpc
From: Daniel Axtens @ 2020-12-01 16:16 UTC (permalink / raw)
To: linux-kernel, linux-mm, linuxppc-dev, kasan-dev, christophe.leroy,
aneesh.kumar, bsingharora
Cc: Daniel Axtens
In-Reply-To: <20201201161632.1234753-1-dja@axtens.net>
KASAN is supported on 32-bit powerpc and the docs should reflect this.
Document s390 support while we're at it.
Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Daniel Axtens <dja@axtens.net>
---
Documentation/dev-tools/kasan.rst | 7 +++++--
Documentation/powerpc/kasan.txt | 12 ++++++++++++
2 files changed, 17 insertions(+), 2 deletions(-)
create mode 100644 Documentation/powerpc/kasan.txt
diff --git a/Documentation/dev-tools/kasan.rst b/Documentation/dev-tools/kasan.rst
index 2b68addaadcd..eaf868094a8e 100644
--- a/Documentation/dev-tools/kasan.rst
+++ b/Documentation/dev-tools/kasan.rst
@@ -19,7 +19,8 @@ out-of-bounds accesses for global variables is only supported since Clang 11.
Tag-based KASAN is only supported in Clang.
Currently generic KASAN is supported for the x86_64, arm64, xtensa, s390 and
-riscv architectures, and tag-based KASAN is supported only for arm64.
+riscv architectures. It is also supported on 32-bit powerpc kernels. Tag-based
+KASAN is supported only on arm64.
Usage
-----
@@ -255,7 +256,9 @@ CONFIG_KASAN_VMALLOC
~~~~~~~~~~~~~~~~~~~~
With ``CONFIG_KASAN_VMALLOC``, KASAN can cover vmalloc space at the
-cost of greater memory usage. Currently this is only supported on x86.
+cost of greater memory usage. Currently this supported on x86, s390
+and 32-bit powerpc. It is optional, except on 32-bit powerpc kernels
+with module support, where it is required.
This works by hooking into vmalloc and vmap, and dynamically
allocating real shadow memory to back the mappings.
diff --git a/Documentation/powerpc/kasan.txt b/Documentation/powerpc/kasan.txt
new file mode 100644
index 000000000000..26bb0e8bb18c
--- /dev/null
+++ b/Documentation/powerpc/kasan.txt
@@ -0,0 +1,12 @@
+KASAN is supported on powerpc on 32-bit only.
+
+32 bit support
+==============
+
+KASAN is supported on both hash and nohash MMUs on 32-bit.
+
+The shadow area sits at the top of the kernel virtual memory space above the
+fixmap area and occupies one eighth of the total kernel virtual memory space.
+
+Instrumentation of the vmalloc area is optional, unless built with modules,
+in which case it is required.
--
2.25.1
^ permalink raw reply related
* [PATCH v9 3/6] kasan: define and use MAX_PTRS_PER_* for early shadow tables
From: Daniel Axtens @ 2020-12-01 16:16 UTC (permalink / raw)
To: linux-kernel, linux-mm, linuxppc-dev, kasan-dev, christophe.leroy,
aneesh.kumar, bsingharora
Cc: Daniel Axtens
In-Reply-To: <20201201161632.1234753-1-dja@axtens.net>
powerpc has a variable number of PTRS_PER_*, set at runtime based
on the MMU that the kernel is booted under.
This means the PTRS_PER_* are no longer constants, and therefore
breaks the build.
Define default MAX_PTRS_PER_*s in the same style as MAX_PTRS_PER_P4D.
As KASAN is the only user at the moment, just define them in the kasan
header, and have them default to PTRS_PER_* unless overridden in arch
code.
Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr>
Suggested-by: Balbir Singh <bsingharora@gmail.com>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Daniel Axtens <dja@axtens.net>
---
include/linux/kasan.h | 18 +++++++++++++++---
mm/kasan/init.c | 6 +++---
2 files changed, 18 insertions(+), 6 deletions(-)
diff --git a/include/linux/kasan.h b/include/linux/kasan.h
index 3df66fdf6662..893d054aad6f 100644
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h
@@ -24,10 +24,22 @@ struct kunit_kasan_expectation {
static inline bool kasan_arch_is_ready(void) { return true; }
#endif
+#ifndef MAX_PTRS_PER_PTE
+#define MAX_PTRS_PER_PTE PTRS_PER_PTE
+#endif
+
+#ifndef MAX_PTRS_PER_PMD
+#define MAX_PTRS_PER_PMD PTRS_PER_PMD
+#endif
+
+#ifndef MAX_PTRS_PER_PUD
+#define MAX_PTRS_PER_PUD PTRS_PER_PUD
+#endif
+
extern unsigned char kasan_early_shadow_page[PAGE_SIZE];
-extern pte_t kasan_early_shadow_pte[PTRS_PER_PTE];
-extern pmd_t kasan_early_shadow_pmd[PTRS_PER_PMD];
-extern pud_t kasan_early_shadow_pud[PTRS_PER_PUD];
+extern pte_t kasan_early_shadow_pte[MAX_PTRS_PER_PTE];
+extern pmd_t kasan_early_shadow_pmd[MAX_PTRS_PER_PMD];
+extern pud_t kasan_early_shadow_pud[MAX_PTRS_PER_PUD];
extern p4d_t kasan_early_shadow_p4d[MAX_PTRS_PER_P4D];
int kasan_populate_early_shadow(const void *shadow_start,
diff --git a/mm/kasan/init.c b/mm/kasan/init.c
index fe6be0be1f76..42bca3d27db8 100644
--- a/mm/kasan/init.c
+++ b/mm/kasan/init.c
@@ -46,7 +46,7 @@ static inline bool kasan_p4d_table(pgd_t pgd)
}
#endif
#if CONFIG_PGTABLE_LEVELS > 3
-pud_t kasan_early_shadow_pud[PTRS_PER_PUD] __page_aligned_bss;
+pud_t kasan_early_shadow_pud[MAX_PTRS_PER_PUD] __page_aligned_bss;
static inline bool kasan_pud_table(p4d_t p4d)
{
return p4d_page(p4d) == virt_to_page(lm_alias(kasan_early_shadow_pud));
@@ -58,7 +58,7 @@ static inline bool kasan_pud_table(p4d_t p4d)
}
#endif
#if CONFIG_PGTABLE_LEVELS > 2
-pmd_t kasan_early_shadow_pmd[PTRS_PER_PMD] __page_aligned_bss;
+pmd_t kasan_early_shadow_pmd[MAX_PTRS_PER_PMD] __page_aligned_bss;
static inline bool kasan_pmd_table(pud_t pud)
{
return pud_page(pud) == virt_to_page(lm_alias(kasan_early_shadow_pmd));
@@ -69,7 +69,7 @@ static inline bool kasan_pmd_table(pud_t pud)
return false;
}
#endif
-pte_t kasan_early_shadow_pte[PTRS_PER_PTE] __page_aligned_bss;
+pte_t kasan_early_shadow_pte[MAX_PTRS_PER_PTE] __page_aligned_bss;
static inline bool kasan_pte_table(pmd_t pmd)
{
--
2.25.1
^ permalink raw reply related
* [PATCH v9 2/6] kasan: allow architectures to provide an outline readiness check
From: Daniel Axtens @ 2020-12-01 16:16 UTC (permalink / raw)
To: linux-kernel, linux-mm, linuxppc-dev, kasan-dev, christophe.leroy,
aneesh.kumar, bsingharora
Cc: Aneesh Kumar K . V, Daniel Axtens
In-Reply-To: <20201201161632.1234753-1-dja@axtens.net>
Allow architectures to define a kasan_arch_is_ready() hook that bails
out of any function that's about to touch the shadow unless the arch
says that it is ready for the memory to be accessed. This is fairly
uninvasive and should have a negligible performance penalty.
This will only work in outline mode, so an arch must specify
HAVE_ARCH_NO_KASAN_INLINE if it requires this.
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Daniel Axtens <dja@axtens.net>
--
I discuss the justfication for this later in the series. Also,
both previous RFCs for ppc64 - by 2 different people - have
needed this trick! See:
- https://lore.kernel.org/patchwork/patch/592820/ # ppc64 hash series
- https://patchwork.ozlabs.org/patch/795211/ # ppc radix series
---
include/linux/kasan.h | 4 ++++
mm/kasan/common.c | 10 ++++++++++
mm/kasan/generic.c | 3 +++
3 files changed, 17 insertions(+)
diff --git a/include/linux/kasan.h b/include/linux/kasan.h
index 30d343b4a40a..3df66fdf6662 100644
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h
@@ -20,6 +20,10 @@ struct kunit_kasan_expectation {
bool report_found;
};
+#ifndef kasan_arch_is_ready
+static inline bool kasan_arch_is_ready(void) { return true; }
+#endif
+
extern unsigned char kasan_early_shadow_page[PAGE_SIZE];
extern pte_t kasan_early_shadow_pte[PTRS_PER_PTE];
extern pmd_t kasan_early_shadow_pmd[PTRS_PER_PMD];
diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index 950fd372a07e..ba7744d3e319 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -117,6 +117,9 @@ void kasan_poison_shadow(const void *address, size_t size, u8 value)
{
void *shadow_start, *shadow_end;
+ if (!kasan_arch_is_ready())
+ return;
+
/*
* Perform shadow offset calculation based on untagged address, as
* some of the callers (e.g. kasan_poison_object_data) pass tagged
@@ -134,6 +137,9 @@ void kasan_unpoison_shadow(const void *address, size_t size)
{
u8 tag = get_tag(address);
+ if (!kasan_arch_is_ready())
+ return;
+
/*
* Perform shadow offset calculation based on untagged address, as
* some of the callers (e.g. kasan_unpoison_object_data) pass tagged
@@ -406,6 +412,10 @@ static bool __kasan_slab_free(struct kmem_cache *cache, void *object,
if (unlikely(cache->flags & SLAB_TYPESAFE_BY_RCU))
return false;
+ /* We can't read the shadow byte if the arch isn't ready */
+ if (!kasan_arch_is_ready())
+ return false;
+
shadow_byte = READ_ONCE(*(s8 *)kasan_mem_to_shadow(object));
if (shadow_invalid(tag, shadow_byte)) {
kasan_report_invalid_free(tagged_object, ip);
diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c
index 248264b9cb76..e87404026b2b 100644
--- a/mm/kasan/generic.c
+++ b/mm/kasan/generic.c
@@ -169,6 +169,9 @@ static __always_inline bool check_memory_region_inline(unsigned long addr,
size_t size, bool write,
unsigned long ret_ip)
{
+ if (!kasan_arch_is_ready())
+ return true;
+
if (unlikely(size == 0))
return true;
--
2.25.1
^ permalink raw reply related
* [PATCH v9 1/6] kasan: allow an architecture to disable inline instrumentation
From: Daniel Axtens @ 2020-12-01 16:16 UTC (permalink / raw)
To: linux-kernel, linux-mm, linuxppc-dev, kasan-dev, christophe.leroy,
aneesh.kumar, bsingharora
Cc: Daniel Axtens
In-Reply-To: <20201201161632.1234753-1-dja@axtens.net>
For annoying architectural reasons, it's very difficult to support inline
instrumentation on powerpc64.
Add a Kconfig flag to allow an arch to disable inline. (It's a bit
annoying to be 'backwards', but I'm not aware of any way to have
an arch force a symbol to be 'n', rather than 'y'.)
Signed-off-by: Daniel Axtens <dja@axtens.net>
---
lib/Kconfig.kasan | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan
index 542a9c18398e..31a0b28f6c2b 100644
--- a/lib/Kconfig.kasan
+++ b/lib/Kconfig.kasan
@@ -9,6 +9,9 @@ config HAVE_ARCH_KASAN_SW_TAGS
config HAVE_ARCH_KASAN_VMALLOC
bool
+config HAVE_ARCH_NO_KASAN_INLINE
+ def_bool n
+
config CC_HAS_KASAN_GENERIC
def_bool $(cc-option, -fsanitize=kernel-address)
@@ -108,6 +111,7 @@ config KASAN_OUTLINE
config KASAN_INLINE
bool "Inline instrumentation"
+ depends on !HAVE_ARCH_NO_KASAN_INLINE
help
Compiler directly inserts code checking shadow memory before
memory accesses. This is faster than outline (in some workloads
--
2.25.1
^ permalink raw reply related
* [PATCH v9 0/6] KASAN for powerpc64 radix
From: Daniel Axtens @ 2020-12-01 16:16 UTC (permalink / raw)
To: linux-kernel, linux-mm, linuxppc-dev, kasan-dev, christophe.leroy,
aneesh.kumar, bsingharora
Cc: Daniel Axtens
Building on the work of Christophe, Aneesh and Balbir, I've ported
KASAN to 64-bit Book3S kernels running on the Radix MMU.
This is a significant reworking of the previous versions. Instead of
the previous approach which supported inline instrumentation, this
series provides only outline instrumentation.
To get around the problem of accessing the shadow region inside code we run
with translations off (in 'real mode'), we we restrict checking to when
translations are enabled. This is done via a new hook in the kasan core and
by excluding larger quantites of arch code from instrumentation. The upside
is that we no longer require that you be able to specify the amount of
physically contiguous memory on the system at compile time. Hopefully this
is a better trade-off. More details in patch 6.
kexec works. Both 64k and 4k pages work. Running as a KVM host works, but
nothing in arch/powerpc/kvm is instrumented. It's also potentially a bit
fragile - if any real mode code paths call out to instrumented code, things
will go boom.
There are 4 failing KUnit tests:
kasan_stack_oob, kasan_alloca_oob_left & kasan_alloca_oob_right - these are
due to not supporting inline instrumentation.
kasan_global_oob - gcc puts the ASAN init code in a section called
'.init_array'. Powerpc64 module loading code goes through and _renames_ any
section beginning with '.init' to begin with '_init' in order to avoid some
complexities around our 24-bit indirect jumps. This means it renames
'.init_array' to '_init_array', and the generic module loading code then
fails to recognise the section as a constructor and thus doesn't run
it. This hack dates back to 2003 and so I'm not going to try to unpick it
in this series. (I suspect this may have previously worked if the code
ended up in .ctors rather than .init_array but I don't keep my old binaries
around so I have no real way of checking.)
Daniel Axtens (6):
kasan: allow an architecture to disable inline instrumentation
kasan: allow architectures to provide an outline readiness check
kasan: define and use MAX_PTRS_PER_* for early shadow tables
kasan: Document support on 32-bit powerpc
powerpc/mm/kasan: rename kasan_init_32.c to init_32.c
powerpc: Book3S 64-bit outline-only KASAN support
^ permalink raw reply
* [PATCH net v3 1/2] ibmvnic: Ensure that SCRQ entry reads are correctly ordered
From: Thomas Falcon @ 2020-12-01 15:52 UTC (permalink / raw)
To: kuba
Cc: cforno12, ljp, ricklind, dnbanerg, tlfalcon, drt, netdev, brking,
sukadev, linuxppc-dev
In-Reply-To: <1606837931-22676-1-git-send-email-tlfalcon@linux.ibm.com>
Ensure that received Subordinate Command-Response Queue (SCRQ)
entries are properly read in order by the driver. These queues
are used in the ibmvnic device to process RX buffer and TX completion
descriptors. dma_rmb barriers have been added after checking for a
pending descriptor to ensure the correct descriptor entry is checked
and after reading the SCRQ descriptor to ensure the entire
descriptor is read before processing.
Fixes: 032c5e82847a ("Driver for IBM System i/p VNIC protocol")
Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
---
drivers/net/ethernet/ibm/ibmvnic.c | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index 2aa40b2..5ea9f5c 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -2403,6 +2403,12 @@ static int ibmvnic_poll(struct napi_struct *napi, int budget)
if (!pending_scrq(adapter, adapter->rx_scrq[scrq_num]))
break;
+ /* The queue entry at the current index is peeked at above
+ * to determine that there is a valid descriptor awaiting
+ * processing. We want to be sure that the current slot
+ * holds a valid descriptor before reading its contents.
+ */
+ dma_rmb();
next = ibmvnic_next_scrq(adapter, adapter->rx_scrq[scrq_num]);
rx_buff =
(struct ibmvnic_rx_buff *)be64_to_cpu(next->
@@ -3098,6 +3104,13 @@ static int ibmvnic_complete_tx(struct ibmvnic_adapter *adapter,
unsigned int pool = scrq->pool_index;
int num_entries = 0;
+ /* The queue entry at the current index is peeked at above
+ * to determine that there is a valid descriptor awaiting
+ * processing. We want to be sure that the current slot
+ * holds a valid descriptor before reading its contents.
+ */
+ dma_rmb();
+
next = ibmvnic_next_scrq(adapter, scrq);
for (i = 0; i < next->tx_comp.num_comps; i++) {
if (next->tx_comp.rcs[i]) {
@@ -3498,6 +3511,11 @@ static union sub_crq *ibmvnic_next_scrq(struct ibmvnic_adapter *adapter,
}
spin_unlock_irqrestore(&scrq->lock, flags);
+ /* Ensure that the entire buffer descriptor has been
+ * loaded before reading its contents
+ */
+ dma_rmb();
+
return entry;
}
--
1.8.3.1
^ permalink raw reply related
* [PATCH net v3 0/2] ibmvnic: Bug fixes for queue descriptor processing
From: Thomas Falcon @ 2020-12-01 15:52 UTC (permalink / raw)
To: kuba
Cc: cforno12, ljp, ricklind, dnbanerg, tlfalcon, drt, netdev, brking,
sukadev, linuxppc-dev
This series resolves a few issues in the ibmvnic driver's
RX buffer and TX completion processing. The first patch
includes memory barriers to synchronize queue descriptor
reads. The second patch fixes a memory leak that could
occur if the device returns a TX completion with an error
code in the descriptor, in which case the respective socket
buffer and other relevant data structures may not be freed
or updated properly.
v3: Correct length of Fixes tags, requested by Jakub Kicinski
v2: Provide more detailed comments explaining specifically what
reads are being ordered, suggested by Michael Ellerman
Thomas Falcon (2):
ibmvnic: Ensure that SCRQ entry reads are correctly ordered
ibmvnic: Fix TX completion error handling
drivers/net/ethernet/ibm/ibmvnic.c | 22 +++++++++++++++++++---
1 file changed, 19 insertions(+), 3 deletions(-)
--
1.8.3.1
^ permalink raw reply
* [PATCH net v3 2/2] ibmvnic: Fix TX completion error handling
From: Thomas Falcon @ 2020-12-01 15:52 UTC (permalink / raw)
To: kuba
Cc: cforno12, ljp, ricklind, dnbanerg, tlfalcon, drt, netdev, brking,
sukadev, linuxppc-dev
In-Reply-To: <1606837931-22676-1-git-send-email-tlfalcon@linux.ibm.com>
TX completions received with an error return code are not
being processed properly. When an error code is seen, do not
proceed to the next completion before cleaning up the existing
entry's data structures.
Fixes: 032c5e82847a ("Driver for IBM System i/p VNIC protocol")
Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
---
drivers/net/ethernet/ibm/ibmvnic.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index 5ea9f5c..10878f8 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -3113,11 +3113,9 @@ static int ibmvnic_complete_tx(struct ibmvnic_adapter *adapter,
next = ibmvnic_next_scrq(adapter, scrq);
for (i = 0; i < next->tx_comp.num_comps; i++) {
- if (next->tx_comp.rcs[i]) {
+ if (next->tx_comp.rcs[i])
dev_err(dev, "tx error %x\n",
next->tx_comp.rcs[i]);
- continue;
- }
index = be32_to_cpu(next->tx_comp.correlators[i]);
if (index & IBMVNIC_TSO_POOL_MASK) {
tx_pool = &adapter->tso_pool[pool];
--
1.8.3.1
^ permalink raw reply related
* Re: [PATCH 1/5] ARM: configs: drop unused BACKLIGHT_GENERIC option
From: Arnd Bergmann @ 2020-12-01 15:50 UTC (permalink / raw)
To: Alexandre Belloni
Cc: tony@atomide.com, linux-kernel@vger.kernel.org,
James.Bottomley@HansenPartnership.com, thierry.reding@gmail.com,
paulus@samba.org, sam@ravnborg.org, daniel.thompson@linaro.org,
linux-omap@vger.kernel.org, Arnd Bergmann, deller@gmx.de,
linux@armlinux.org.uk, Krzysztof Kozlowski, jonathanh@nvidia.com,
ludovic.desroches@microchip.com, arm-soc, Catalin Marinas,
linux-mips@vger.kernel.org, will@kernel.org, mripard@kernel.org,
ZHIZHIKIN Andrey, linux-tegra@vger.kernel.org,
lee.jones@linaro.org, wens@csie.org,
linux-arm-kernel@lists.infradead.org, jernej.skrabec@siol.net,
tsbogend@alpha.franken.de, linux-parisc@vger.kernel.org,
emil.l.velikov@gmail.com, nicolas.ferre@microchip.com,
Olof Johansson, linuxppc-dev@lists.ozlabs.org
In-Reply-To: <20201201154139.GF2401593@piout.net>
On Tue, Dec 1, 2020 at 4:41 PM Alexandre Belloni
<alexandre.belloni@bootlin.com> wrote:
> On 01/12/2020 14:40:53+0000, Catalin Marinas wrote:
> > On Mon, Nov 30, 2020 at 07:50:25PM +0000, ZHIZHIKIN Andrey wrote:
> > > From Krzysztof Kozlowski <krzk@kernel.org>:
> > I tried to convince them before, it didn't work. I guess they don't like
> > to be spammed ;).
>
> The first rule of arm-soc is: you do not talk about arm@ and soc@
I don't mind having the addresses documented better, but it needs to
be done in a way that avoids having any patch for arch/arm*/boot/dts
and arch/arm/*/configs Cc:d to soc@kernel.org.
If anyone has suggestions for how to do that, let me know.
> > Or rather, SoC-specific patches, even to defconfig,
> > should go through the specific SoC maintainers. However, there are
> > occasional defconfig patches which are more generic or affecting
> > multiple SoCs. I just ignore them as the arm64 defconfig is usually
> > handled by the arm-soc folk (when I need a defconfig change, I go for
> > arch/arm64/Kconfig directly ;)).
>
> IIRC, the plan was indeed to get defconfig changes through the platform
> sub-trees. It is also supposed to be how multi_v5 and multi_v7 are
> handled and they will take care of the merge.
For cross-platform changes like this one, I'm definitely happy to
pick up the patch directly from soc@kernel.org, or from mailing
list if I know about it.
We usually do the merges for the soc tree in batches and rely
on patchwork to keep track of what I'm missing, so if Olof and
I are just on Cc to a mail, we might have forgotten about it
by the time we do the next merges.
Arnd
^ permalink raw reply
* Re: [PATCH 1/5] ARM: configs: drop unused BACKLIGHT_GENERIC option
From: Alexandre Belloni @ 2020-12-01 15:41 UTC (permalink / raw)
To: Catalin Marinas
Cc: tony@atomide.com, linux-kernel@vger.kernel.org,
James.Bottomley@HansenPartnership.com, thierry.reding@gmail.com,
paulus@samba.org, sam@ravnborg.org, daniel.thompson@linaro.org,
linux-omap@vger.kernel.org, Arnd Bergmann, deller@gmx.de,
linux@armlinux.org.uk, Krzysztof Kozlowski, jonathanh@nvidia.com,
ludovic.desroches@microchip.com, arm, linux-mips@vger.kernel.org,
will@kernel.org, mripard@kernel.org, ZHIZHIKIN Andrey,
linux-tegra@vger.kernel.org, lee.jones@linaro.org, wens@csie.org,
linux-arm-kernel@lists.infradead.org, jernej.skrabec@siol.net,
tsbogend@alpha.franken.de, linux-parisc@vger.kernel.org,
emil.l.velikov@gmail.com, nicolas.ferre@microchip.com,
Olof Johansson, linuxppc-dev@lists.ozlabs.org
In-Reply-To: <20201201144052.GE31404@gaia>
On 01/12/2020 14:40:53+0000, Catalin Marinas wrote:
> On Mon, Nov 30, 2020 at 07:50:25PM +0000, ZHIZHIKIN Andrey wrote:
> > From Krzysztof Kozlowski <krzk@kernel.org>:
> > > On Mon, Nov 30, 2020 at 03:21:33PM +0000, Andrey Zhizhikin wrote:
> > > > Commit 7ecdea4a0226 ("backlight: generic_bl: Remove this driver as it is
> > > > unused") removed geenric_bl driver from the tree, together with
> > > > corresponding config option.
> > > >
> > > > Remove BACKLIGHT_GENERIC config item from all ARM configurations.
> > > >
> > > > Fixes: 7ecdea4a0226 ("backlight: generic_bl: Remove this driver as it
> > > > is unused")
> > > > Cc: Sam Ravnborg <sam@ravnborg.org>
> > > > Signed-off-by: Andrey Zhizhikin
> > > > <andrey.zhizhikin@leica-geosystems.com>
> > > > ---
> > > > arch/arm/configs/at91_dt_defconfig | 1 -
> > > > arch/arm/configs/cm_x300_defconfig | 1 -
> > > > arch/arm/configs/colibri_pxa300_defconfig | 1 -
> > > > arch/arm/configs/jornada720_defconfig | 1 -
> > > > arch/arm/configs/magician_defconfig | 1 -
> > > > arch/arm/configs/mini2440_defconfig | 1 -
> > > > arch/arm/configs/omap2plus_defconfig | 1 -
> > > > arch/arm/configs/pxa3xx_defconfig | 1 -
> > > > arch/arm/configs/qcom_defconfig | 1 -
> > > > arch/arm/configs/sama5_defconfig | 1 -
> > > > arch/arm/configs/sunxi_defconfig | 1 -
> > > > arch/arm/configs/tegra_defconfig | 1 -
> > > > arch/arm/configs/u8500_defconfig | 1 -
> > > > 13 files changed, 13 deletions(-)
> > >
> > > You need to send it to arm-soc maintainers, otherwise no one might feel
> > > responsible enough to pick it up.
> >
> > Good point, thanks a lot!
> >
> > I was not aware of the fact that there is a separate ML that should
> > receive patches targeted ARM SOCs. Can you (or anyone else) please
> > share it, so I can re-send it there as well?
>
> It's not a mailing list as such (with archives etc.), just an alias to
> the arm-soc maintainers: arm@kernel.org.
>
> > > Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
> > >
> > > +CC Arnd and Olof,
> > >
> > > Dear Arnd and Olof,
> > >
> > > Maybe it is worth to add arm-soc entry to the MAINTAINERS file?
> > > Otherwise how one could get your email address? Not mentioning the
> > > secret-soc address. :)
>
> I tried to convince them before, it didn't work. I guess they don't like
> to be spammed ;).
The first rule of arm-soc is: you do not talk about arm@ and soc@
> Or rather, SoC-specific patches, even to defconfig,
> should go through the specific SoC maintainers. However, there are
> occasional defconfig patches which are more generic or affecting
> multiple SoCs. I just ignore them as the arm64 defconfig is usually
> handled by the arm-soc folk (when I need a defconfig change, I go for
> arch/arm64/Kconfig directly ;)).
>
IIRC, the plan was indeed to get defconfig changes through the platform
sub-trees. It is also supposed to be how multi_v5 and multi_v7 are
handled and they will take care of the merge.
--
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
^ permalink raw reply
* Re: [PATCH v6 0/5] PCI: Unify ECAM constants in native PCI Express drivers
From: Lorenzo Pieralisi @ 2020-12-01 15:34 UTC (permalink / raw)
To: Bjorn Helgaas, Krzysztof Wilczyński
Cc: Heiko Stuebner, Shawn Lin, Paul Mackerras, Thomas Petazzoni,
Jonathan Chocron, Toan Le, Will Deacon, Rob Herring,
Lorenzo Pieralisi, Michal Simek, linux-rockchip,
bcm-kernel-feedback-list, Jonathan Derrick, linux-pci, Ray Jui,
Florian Fainelli, linux-rpi-kernel, Jonathan Cameron,
linux-arm-kernel, Scott Branden, Zhou Wang, Robert Richter,
linuxppc-dev, Nicolas Saenz Julienne
In-Reply-To: <20201129230743.3006978-1-kw@linux.com>
On Sun, 29 Nov 2020 23:07:38 +0000, Krzysztof Wilczyński wrote:
> Unify ECAM-related constants into a single set of standard constants
> defining memory address shift values for the byte-level address that can
> be used when accessing the PCI Express Configuration Space, and then
> move native PCI Express controller drivers to use newly introduced
> definitions retiring any driver-specific ones.
>
> The ECAM ("Enhanced Configuration Access Mechanism") is defined by the
> PCI Express specification (see PCI Express Base Specification, Revision
> 5.0, Version 1.0, Section 7.2.2, p. 676), thus most hardware should
> implement it the same way.
>
> [...]
Applied to pci/ecam, thanks!
[1/5] PCI: Unify ECAM constants in native PCI Express drivers
https://git.kernel.org/lpieralisi/pci/c/f3c07cf692
[2/5] PCI: thunder-pem: Add constant for custom ".bus_shift" initialiser
https://git.kernel.org/lpieralisi/pci/c/3c38579263
[3/5] PCI: iproc: Convert to use the new ECAM constants
https://git.kernel.org/lpieralisi/pci/c/333ec9d3cc
[4/5] PCI: vmd: Update type of the __iomem pointers
https://git.kernel.org/lpieralisi/pci/c/89094c12ea
[5/5] PCI: xgene: Removed unused ".bus_shift" initialisers from pci-xgene.c
https://git.kernel.org/lpieralisi/pci/c/3dc62532a5
Thanks,
Lorenzo
^ permalink raw reply
* [PATCH] selftests/powerpc: update .gitignore
From: Daniel Axtens @ 2020-12-01 14:44 UTC (permalink / raw)
To: linuxppc-dev; +Cc: Daniel Axtens
I did an in-place build of the self-tests and found that it left
the tree dirty.
Add missed test binaries to .gitignore
Signed-off-by: Daniel Axtens <dja@axtens.net>
---
tools/testing/selftests/powerpc/nx-gzip/.gitignore | 3 +++
tools/testing/selftests/powerpc/security/.gitignore | 1 +
tools/testing/selftests/powerpc/signal/.gitignore | 1 +
tools/testing/selftests/powerpc/syscalls/.gitignore | 1 +
4 files changed, 6 insertions(+)
create mode 100644 tools/testing/selftests/powerpc/nx-gzip/.gitignore
diff --git a/tools/testing/selftests/powerpc/nx-gzip/.gitignore b/tools/testing/selftests/powerpc/nx-gzip/.gitignore
new file mode 100644
index 000000000000..886d522d52df
--- /dev/null
+++ b/tools/testing/selftests/powerpc/nx-gzip/.gitignore
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0-only
+gunz_test
+gzfht_test
diff --git a/tools/testing/selftests/powerpc/security/.gitignore b/tools/testing/selftests/powerpc/security/.gitignore
index 4257a1f156bb..93614b125ded 100644
--- a/tools/testing/selftests/powerpc/security/.gitignore
+++ b/tools/testing/selftests/powerpc/security/.gitignore
@@ -1,3 +1,4 @@
# SPDX-License-Identifier: GPL-2.0-only
rfi_flush
entry_flush
+spectre_v2
diff --git a/tools/testing/selftests/powerpc/signal/.gitignore b/tools/testing/selftests/powerpc/signal/.gitignore
index 405b5364044c..ce3375cd8e73 100644
--- a/tools/testing/selftests/powerpc/signal/.gitignore
+++ b/tools/testing/selftests/powerpc/signal/.gitignore
@@ -3,3 +3,4 @@ signal
signal_tm
sigfuz
sigreturn_vdso
+sig_sc_double_restart
diff --git a/tools/testing/selftests/powerpc/syscalls/.gitignore b/tools/testing/selftests/powerpc/syscalls/.gitignore
index b00cab225476..a1e19ccdef84 100644
--- a/tools/testing/selftests/powerpc/syscalls/.gitignore
+++ b/tools/testing/selftests/powerpc/syscalls/.gitignore
@@ -1,2 +1,3 @@
# SPDX-License-Identifier: GPL-2.0-only
ipc_unmuxed
+rtas_filter
--
2.25.1
^ permalink raw reply related
* [PATCH] powerpc/feature-fixups: use a semicolon rather than a comma
From: Daniel Axtens @ 2020-12-01 14:43 UTC (permalink / raw)
To: linuxppc-dev; +Cc: Nick Piggin, Daniel Axtens
In a bunch of our security flushes, we use a comma rather than
a semicolon to 'terminate' an assignment. Nothing breaks, but
checkpatch picks it up if you copy it into another flush.
Switch to semicolons for ending statements.
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Russell Currey <ruscur@russell.cc>
Signed-off-by: Daniel Axtens <dja@axtens.net>
---
arch/powerpc/lib/feature-fixups.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/arch/powerpc/lib/feature-fixups.c b/arch/powerpc/lib/feature-fixups.c
index 321c12a9ef6b..47821055b94c 100644
--- a/arch/powerpc/lib/feature-fixups.c
+++ b/arch/powerpc/lib/feature-fixups.c
@@ -124,7 +124,7 @@ static void do_stf_entry_barrier_fixups(enum stf_barrier_type types)
long *start, *end;
int i;
- start = PTRRELOC(&__start___stf_entry_barrier_fixup),
+ start = PTRRELOC(&__start___stf_entry_barrier_fixup);
end = PTRRELOC(&__stop___stf_entry_barrier_fixup);
instrs[0] = 0x60000000; /* nop */
@@ -176,7 +176,7 @@ static void do_stf_exit_barrier_fixups(enum stf_barrier_type types)
long *start, *end;
int i;
- start = PTRRELOC(&__start___stf_exit_barrier_fixup),
+ start = PTRRELOC(&__start___stf_exit_barrier_fixup);
end = PTRRELOC(&__stop___stf_exit_barrier_fixup);
instrs[0] = 0x60000000; /* nop */
@@ -344,7 +344,7 @@ void do_rfi_flush_fixups(enum l1d_flush_type types)
long *start, *end;
int i;
- start = PTRRELOC(&__start___rfi_flush_fixup),
+ start = PTRRELOC(&__start___rfi_flush_fixup);
end = PTRRELOC(&__stop___rfi_flush_fixup);
instrs[0] = 0x60000000; /* nop */
@@ -417,7 +417,7 @@ void do_barrier_nospec_fixups(bool enable)
{
void *start, *end;
- start = PTRRELOC(&__start___barrier_nospec_fixup),
+ start = PTRRELOC(&__start___barrier_nospec_fixup);
end = PTRRELOC(&__stop___barrier_nospec_fixup);
do_barrier_nospec_fixups_range(enable, start, end);
--
2.25.1
^ permalink raw reply related
* Re: [PATCH 1/5] ARM: configs: drop unused BACKLIGHT_GENERIC option
From: Catalin Marinas @ 2020-12-01 14:40 UTC (permalink / raw)
To: ZHIZHIKIN Andrey
Cc: alexandre.belloni@bootlin.com, tony@atomide.com,
linux-kernel@vger.kernel.org,
James.Bottomley@HansenPartnership.com, thierry.reding@gmail.com,
paulus@samba.org, sam@ravnborg.org, daniel.thompson@linaro.org,
linux-omap@vger.kernel.org, Arnd Bergmann, deller@gmx.de,
linux@armlinux.org.uk, Krzysztof Kozlowski, jonathanh@nvidia.com,
ludovic.desroches@microchip.com, arm, linux-mips@vger.kernel.org,
will@kernel.org, mripard@kernel.org, linux-tegra@vger.kernel.org,
lee.jones@linaro.org, wens@csie.org,
linux-arm-kernel@lists.infradead.org, jernej.skrabec@siol.net,
tsbogend@alpha.franken.de, linux-parisc@vger.kernel.org,
emil.l.velikov@gmail.com, nicolas.ferre@microchip.com,
Olof Johansson, linuxppc-dev@lists.ozlabs.org
In-Reply-To: <AM6PR06MB4691EC52BA41B86AB16EE14FA6F50@AM6PR06MB4691.eurprd06.prod.outlook.com>
On Mon, Nov 30, 2020 at 07:50:25PM +0000, ZHIZHIKIN Andrey wrote:
> From Krzysztof Kozlowski <krzk@kernel.org>:
> > On Mon, Nov 30, 2020 at 03:21:33PM +0000, Andrey Zhizhikin wrote:
> > > Commit 7ecdea4a0226 ("backlight: generic_bl: Remove this driver as it is
> > > unused") removed geenric_bl driver from the tree, together with
> > > corresponding config option.
> > >
> > > Remove BACKLIGHT_GENERIC config item from all ARM configurations.
> > >
> > > Fixes: 7ecdea4a0226 ("backlight: generic_bl: Remove this driver as it
> > > is unused")
> > > Cc: Sam Ravnborg <sam@ravnborg.org>
> > > Signed-off-by: Andrey Zhizhikin
> > > <andrey.zhizhikin@leica-geosystems.com>
> > > ---
> > > arch/arm/configs/at91_dt_defconfig | 1 -
> > > arch/arm/configs/cm_x300_defconfig | 1 -
> > > arch/arm/configs/colibri_pxa300_defconfig | 1 -
> > > arch/arm/configs/jornada720_defconfig | 1 -
> > > arch/arm/configs/magician_defconfig | 1 -
> > > arch/arm/configs/mini2440_defconfig | 1 -
> > > arch/arm/configs/omap2plus_defconfig | 1 -
> > > arch/arm/configs/pxa3xx_defconfig | 1 -
> > > arch/arm/configs/qcom_defconfig | 1 -
> > > arch/arm/configs/sama5_defconfig | 1 -
> > > arch/arm/configs/sunxi_defconfig | 1 -
> > > arch/arm/configs/tegra_defconfig | 1 -
> > > arch/arm/configs/u8500_defconfig | 1 -
> > > 13 files changed, 13 deletions(-)
> >
> > You need to send it to arm-soc maintainers, otherwise no one might feel
> > responsible enough to pick it up.
>
> Good point, thanks a lot!
>
> I was not aware of the fact that there is a separate ML that should
> receive patches targeted ARM SOCs. Can you (or anyone else) please
> share it, so I can re-send it there as well?
It's not a mailing list as such (with archives etc.), just an alias to
the arm-soc maintainers: arm@kernel.org.
> > Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
> >
> > +CC Arnd and Olof,
> >
> > Dear Arnd and Olof,
> >
> > Maybe it is worth to add arm-soc entry to the MAINTAINERS file?
> > Otherwise how one could get your email address? Not mentioning the
> > secret-soc address. :)
I tried to convince them before, it didn't work. I guess they don't like
to be spammed ;). Or rather, SoC-specific patches, even to defconfig,
should go through the specific SoC maintainers. However, there are
occasional defconfig patches which are more generic or affecting
multiple SoCs. I just ignore them as the arm64 defconfig is usually
handled by the arm-soc folk (when I need a defconfig change, I go for
arch/arm64/Kconfig directly ;)).
Anyway, I still think that we should add a MAINTAINERS entry for
arch/arm64/configs/defconfig and arch/arm64/Kconfig.platforms.
--
Catalin
^ permalink raw reply
* Re: [PATCH v8 05/12] mm: HUGE_VMAP arch support cleanup
From: Catalin Marinas @ 2020-12-01 14:21 UTC (permalink / raw)
To: Nicholas Piggin
Cc: linux-arch, H. Peter Anvin, Ingo Molnar, Will Deacon, x86,
linux-kernel, Christoph Hellwig, linux-mm, Zefan Li,
Borislav Petkov, Jonathan Cameron, Andrew Morton, linuxppc-dev,
Thomas Gleixner, linux-arm-kernel
In-Reply-To: <20201128152559.999540-6-npiggin@gmail.com>
On Sun, Nov 29, 2020 at 01:25:52AM +1000, Nicholas Piggin wrote:
> This changes the awkward approach where architectures provide init
> functions to determine which levels they can provide large mappings for,
> to one where the arch is queried for each call.
>
> This removes code and indirection, and allows constant-folding of dead
> code for unsupported levels.
>
> This also adds a prot argument to the arch query. This is unused
> currently but could help with some architectures (e.g., some powerpc
> processors can't map uncacheable memory with large pages).
>
> Cc: linuxppc-dev@lists.ozlabs.org
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Will Deacon <will@kernel.org>
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Borislav Petkov <bp@alien8.de>
> Cc: x86@kernel.org
> Cc: "H. Peter Anvin" <hpa@zytor.com>
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
> arch/arm64/include/asm/vmalloc.h | 8 +++
> arch/arm64/mm/mmu.c | 10 +--
For arm64:
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
^ permalink raw reply
* Re: [RFC PATCH 01/14] ftrace: Fix updating FTRACE_FL_TRAMP
From: Naveen N. Rao @ 2020-12-01 13:46 UTC (permalink / raw)
To: Steven Rostedt; +Cc: linuxppc-dev, linux-kernel
In-Reply-To: <20201130212346.31e2a8b7@oasis.local.home>
Steven Rostedt wrote:
> On Thu, 26 Nov 2020 23:38:38 +0530
> "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> wrote:
>
>> On powerpc, kprobe-direct.tc triggered FTRACE_WARN_ON() in
>> ftrace_get_addr_new() followed by the below message:
>> Bad trampoline accounting at: 000000004222522f (wake_up_process+0xc/0x20) (f0000001)
>>
>> The set of steps leading to this involved:
>> - modprobe ftrace-direct-too
>> - enable_probe
>> - modprobe ftrace-direct
>> - rmmod ftrace-direct <-- trigger
>>
>> The problem turned out to be that we were not updating flags in the
>> ftrace record properly. From the above message about the trampoline
>> accounting being bad, it can be seen that the ftrace record still has
>> FTRACE_FL_TRAMP set though ftrace-direct module is going away. This
>> happens because we are checking if any ftrace_ops has the
>> FTRACE_FL_TRAMP flag set _before_ updating the filter hash.
>>
>> The fix for this is to look for any _other_ ftrace_ops that also needs
>> FTRACE_FL_TRAMP.
>
> I'm applying this now and sending this for -rc and stable.
>
> The code worked on x86 because x86 has a way to make all users use
> trampolines, so this was never an issue (everything has a trampoline).
> I modified the kernel so that x86 would not create its own trampoline
> (see the weak function arch_ftrace_update_trampoline(), and I was able
> to reproduce the bug.
Good to know that you were able to reproduce this.
>
> I'm adding:
>
> Cc: stable@vger.kernel.org
> Fixes: a124692b698b0 ("ftrace: Enable trampoline when rec count returns back to one")
That looks good to me. Thanks for picking the two patches and for your
review on the others!
- Naveen
^ permalink raw reply
* Re: [PATCH v2 1/2] kbuild: Hoist '--orphan-handling' into Kconfig
From: Masahiro Yamada @ 2020-12-01 13:28 UTC (permalink / raw)
To: Kees Cook
Cc: Michal Marek, Linux Kbuild mailing list, Catalin Marinas, X86 ML,
Nick Desaulniers, Russell King, Linux Kernel Mailing List,
linuxppc-dev, Arvind Sankar, Ingo Molnar, Borislav Petkov,
clang-built-linux, Nathan Chancellor, Will Deacon,
Thomas Gleixner, linux-arm-kernel
In-Reply-To: <202011201607.75FA476@keescook>
On Sat, Nov 21, 2020 at 9:08 AM Kees Cook <keescook@chromium.org> wrote:
>
> On Thu, Nov 19, 2020 at 01:46:56PM -0700, Nathan Chancellor wrote:
> > Currently, '--orphan-handling=warn' is spread out across four different
> > architectures in their respective Makefiles, which makes it a little
> > unruly to deal with in case it needs to be disabled for a specific
> > linker version (in this case, ld.lld 10.0.1).
> >
> > To make it easier to control this, hoist this warning into Kconfig and
> > the main Makefile so that disabling it is simpler, as the warning will
> > only be enabled in a couple places (main Makefile and a couple of
> > compressed boot folders that blow away LDFLAGS_vmlinx) and making it
> > conditional is easier due to Kconfig syntax. One small additional
> > benefit of this is saving a call to ld-option on incremental builds
> > because we will have already evaluated it for CONFIG_LD_ORPHAN_WARN.
> >
> > To keep the list of supported architectures the same, introduce
> > CONFIG_ARCH_WANT_LD_ORPHAN_WARN, which an architecture can select to
> > gain this automatically after all of the sections are specified and size
> > asserted. A special thanks to Kees Cook for the help text on this
> > config.
> >
> > Link: https://github.com/ClangBuiltLinux/linux/issues/1187
> > Acked-by: Kees Cook <keescook@chromium.org>
> > Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
> > Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
> > Tested-by: Nick Desaulniers <ndesaulniers@google.com>
> > Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
>
> Masahiro, do you want to take these to get them to Linus for v5.10? I
> can send them if you'd prefer.
>
Sorry for the delay.
Applied to linux-kbuild.
> -Kees
>
> --
> Kees Cook
>
> --
> You received this message because you are subscribed to the Google Groups "Clang Built Linux" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to clang-built-linux+unsubscribe@googlegroups.com.
> To view this discussion on the web visit https://groups.google.com/d/msgid/clang-built-linux/202011201607.75FA476%40keescook.
--
Best Regards
Masahiro Yamada
^ permalink raw reply
* Re: [PATCH v2 2/2] kbuild: Disable CONFIG_LD_ORPHAN_WARN for ld.lld 10.0.1
From: Masahiro Yamada @ 2020-12-01 13:31 UTC (permalink / raw)
To: Kees Cook
Cc: Michal Marek, kernelci . org bot, Linux Kbuild mailing list,
Catalin Marinas, Mark Brown,
maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT), Nick Desaulniers,
Russell King, LKML, linuxppc-dev, Arvind Sankar, Ingo Molnar,
Borislav Petkov, clang-built-linux, Nathan Chancellor,
Will Deacon, Thomas Gleixner, Linux ARM
In-Reply-To: <202011241421.A2F3062A70@keescook>
On Wed, Nov 25, 2020 at 7:22 AM Kees Cook <keescook@chromium.org> wrote:
>
> On Thu, Nov 19, 2020 at 01:13:27PM -0800, Nick Desaulniers wrote:
> > On Thu, Nov 19, 2020 at 12:57 PM Nathan Chancellor
> > <natechancellor@gmail.com> wrote:
> > >
> > > ld.lld 10.0.1 spews a bunch of various warnings about .rela sections,
> > > along with a few others. Newer versions of ld.lld do not have these
> > > warnings. As a result, do not add '--orphan-handling=warn' to
> > > LDFLAGS_vmlinux if ld.lld's version is not new enough.
> > >
> > > Link: https://github.com/ClangBuiltLinux/linux/issues/1187
> > > Link: https://github.com/ClangBuiltLinux/linux/issues/1193
> > > Reported-by: Arvind Sankar <nivedita@alum.mit.edu>
> > > Reported-by: kernelci.org bot <bot@kernelci.org>
> > > Reported-by: Mark Brown <broonie@kernel.org>
> > > Reviewed-by: Kees Cook <keescook@chromium.org>
> > > Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
> >
> > Thanks for the additions in v2.
> > Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
>
> I'm going to carry this for a few days in -next, and if no one screams,
> ask Linus to pull it for v5.10-rc6.
>
> Thanks!
>
> --
> Kees Cook
Sorry for the delay.
Applied to linux-kbuild.
But, I already see this in linux-next.
Please let me know if I should drop it from my tree.
--
Best Regards
Masahiro Yamada
^ permalink raw reply
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