* [PATCH v8 0/4] KASAN for powerpc64 radix
From: Daniel Axtens @ 2020-03-06 13:33 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 provides full inline instrumentation on radix, but does require
that you be able to specify the amount of physically contiguous memory
on the system at compile time. More details in patch 4.
One quirk that I've noticed is that detection of invalid accesses to
module globals are currently broken - everything is permitted. I'm
sure this used to work, but it doesn't atm and this is why: 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.)
v8: Rejig patch 4 commit message, thanks Mikey.
Various tweaks to patch 4: fix some potential hangs, clean up
some code, fix a trivial bug, and also have another crack at
correct stack-walking based on what other arches do. Some very
minor tweaks, and a review from Christophe.
v7: Tweaks from Christophe, fix issues detected by snowpatch.
v6: Rebase on the latest changes in powerpc/merge. Minor tweaks
to the documentation. Small tweaks to the header to work
with the kasan_late_init() function that Christophe added
for 32-bit kasan-vmalloc support.
No functional change.
v5: ptdump support. More cleanups, tweaks and fixes, thanks
Christophe. Details in patch 4.
I have seen another stack walk splat, but I don't think it's
related to the patch set, I think there's a bug somewhere else,
probably in stack frame manipulation in the kernel or (more
unlikely) in the compiler.
v4: More cleanups, split renaming out, clarify bits and bobs.
Drop the stack walk disablement, that isn't needed. No other
functional change.
v3: Reduce the overly ambitious scope of the MAX_PTRS change.
Document more things, including around why some of the
restrictions apply.
Clean up the code more, thanks Christophe.
v2: The big change is the introduction of tree-wide(ish)
MAX_PTRS_PER_{PTE,PMD,PUD} macros in preference to the previous
approach, which was for the arch to override the page table array
definitions with their own. (And I squashed the annoying
intermittent crash!)
Apart from that there's just a lot of cleanup. Christophe, I've
addressed most of what you asked for and I will reply to your v1
emails to clarify what remains unchanged.
^ permalink raw reply
* [PATCH v8 1/4] kasan: define and use MAX_PTRS_PER_* for early shadow tables
From: Daniel Axtens @ 2020-03-06 13:33 UTC (permalink / raw)
To: linux-kernel, linux-mm, linuxppc-dev, kasan-dev, christophe.leroy,
aneesh.kumar, bsingharora
Cc: Daniel Axtens
In-Reply-To: <20200306133340.9181-1-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 5cde9e7c2664..b3a4500633f5 100644
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h
@@ -14,10 +14,22 @@ struct task_struct;
#include <asm/kasan.h>
#include <asm/pgtable.h>
+#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 ce45c491ebcd..8b54a96d3b3e 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)
{
--
2.20.1
^ permalink raw reply related
* [PATCH v8 2/4] kasan: Document support on 32-bit powerpc
From: Daniel Axtens @ 2020-03-06 13:33 UTC (permalink / raw)
To: linux-kernel, linux-mm, linuxppc-dev, kasan-dev, christophe.leroy,
aneesh.kumar, bsingharora
Cc: Daniel Axtens
In-Reply-To: <20200306133340.9181-1-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>
---
Changes since v5:
- rebase - riscv has now got support.
- document s390 support while we're at it
- clarify when kasan_vmalloc support is required
---
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 c652d740735d..012ef3d91d1f 100644
--- a/Documentation/dev-tools/kasan.rst
+++ b/Documentation/dev-tools/kasan.rst
@@ -22,7 +22,8 @@ global variables yet.
Tag-based KASAN is only supported in Clang and requires version 7.0.0 or later.
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.
--
2.20.1
^ permalink raw reply related
* [PATCH v8 3/4] powerpc/mm/kasan: rename kasan_init_32.c to init_32.c
From: Daniel Axtens @ 2020-03-06 13:33 UTC (permalink / raw)
To: linux-kernel, linux-mm, linuxppc-dev, kasan-dev, christophe.leroy,
aneesh.kumar, bsingharora
Cc: Daniel Axtens
In-Reply-To: <20200306133340.9181-1-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 6577897673dd..36a4e1b10b2d 100644
--- a/arch/powerpc/mm/kasan/Makefile
+++ b/arch/powerpc/mm/kasan/Makefile
@@ -2,4 +2,4 @@
KASAN_SANITIZE := n
-obj-$(CONFIG_PPC32) += kasan_init_32.o
+obj-$(CONFIG_PPC32) += init_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
--
2.20.1
^ permalink raw reply related
* [PATCH v8 4/4] powerpc: Book3S 64-bit "heavyweight" KASAN support
From: Daniel Axtens @ 2020-03-06 13:33 UTC (permalink / raw)
To: linux-kernel, linux-mm, linuxppc-dev, kasan-dev, christophe.leroy,
aneesh.kumar, bsingharora
Cc: Daniel Axtens
In-Reply-To: <20200306133340.9181-1-dja@axtens.net>
Implement a limited form of KASAN for Book3S 64-bit machines running under
the Radix MMU:
- Set aside the last 1/8th of the first contiguous block of physical
memory to provide writable shadow for the linear map. For annoying
reasons documented below, the memory size must be specified at compile
time.
- 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
back all kernel addresses with real memory - only linear map and
vmalloc. On boot, set up a single page of read-only shadow that marks
all these 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 in real mode after booting. Most notably a lot of KVM
runs in real mode, and it would be good to be able to instrument it.
- Because code runs in real mode after boot, the offset has to point to
valid memory both in and out of real mode.
[ppc64 mm note: The kernel installs a linear mapping at effective
address c000... onward. 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.]
One approach is just to give up on inline instrumentation. This way all
checks can be delayed until after everything set is up correctly, and the
address-to-shadow calculations can be overridden. However, the features and
speed boost provided by inline instrumentation are worth trying to do
better.
If _at compile time_ it is known how much contiguous physical memory a
system has, the top 1/8th of the first block of physical memory can be set
aside for the shadow. This is a big hammer and comes with 3 big
consequences:
- there's no nice way to handle physically discontiguous memory, so only
the first physical memory block can be used.
- kernels will simply fail to boot on machines with less memory than
specified when compiling.
- kernels running on machines with more memory than specified when
compiling will simply ignore the extra memory.
Despite the limitations, it can still find bugs,
e.g. http://patchwork.ozlabs.org/patch/1103775/
At the moment, this physical memory limit must be set _even for outline
mode_. This may be changed in a later series - a different implementation
could be added for outline mode that dynamically allocates shadow at a
fixed offset. For example, see https://patchwork.ozlabs.org/patch/795211/
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Balbir Singh <bsingharora@gmail.com> # ppc64 out-of-line radix version
Cc: Christophe Leroy <christophe.leroy@c-s.fr> # ppc32 version
Reviewed-by: <christophe.leroy@c-s.fr> # focussed mainly on Documentation
and things impacting PPC32
Signed-off-by: Daniel Axtens <dja@axtens.net>
---
Changes since v7:
- Don't instrument arch/powerpc/kernel/paca.c, it can lead to hangs. Also
don't instrument setup_64.c; it's too early to be safe.
- Reword this commit message, thanks Mikey.
- Reinsert some tidier stack walking code, with hopefully some better
justification. Certainly it is a common, cross-platform sort of issue.
- Fix a stupid bug in early printing where I multiplied by SZ_1M rather than
divided.
- Make the memory reservation code FLATMEM friendly.
- Kconfig tweaks, thanks Christophe.
Changes since v6:
- rework kasan_late_init support, which also fixes book3e problem that snowpatch
picked up (I think)
- fix a checkpatch error that snowpatch picked up
- don't needlessly move the include in kasan.h
Changes since v5:
- rebase on powerpc/merge, with Christophe's latest changes integrating
kasan-vmalloc
- documentation tweaks based on latest 32-bit changes
Changes since v4:
- fix some ppc32 build issues
- support ptdump
- clean up the header file. It turns out we don't need or use KASAN_SHADOW_SIZE,
so just dump it, and make KASAN_SHADOW_END the thing that varies between 32
and 64 bit. As part of this, make sure KASAN_SHADOW_OFFSET is only configured for
32 bit - it is calculated in the Makefile for ppc64.
- various cleanups
Changes since v3:
- Address further feedback from Christophe.
- Drop changes to stack walking, it looks like the issue I observed is
related to that particular stack, not stack-walking generally.
Changes since v2:
- Address feedback from Christophe around cleanups and docs.
- Address feedback from Balbir: at this point I don't have a good solution
for the issues you identify around the limitations of the inline implementation
but I think that it's worth trying to get the stack instrumentation support.
I'm happy to have an alternative and more flexible outline mode - I had
envisoned this would be called 'lightweight' mode as it imposes fewer restrictions.
I've linked to your implementation. I think it's best to add it in a follow-up series.
- Made the default PHYS_MEM_SIZE_FOR_KASAN value 1024MB. I think most people have
guests with at least that much memory in the Radix 64s case so it's a much
saner default - it means that if you just turn on KASAN without reading the
docs you're much more likely to have a bootable kernel, which you will never
have if the value is set to zero! I'm happy to bikeshed the value if we want.
Changes since v1:
- Landed kasan vmalloc support upstream
- Lots of feedback from Christophe.
Changes since the rfc:
- Boots real and virtual hardware, kvm works.
- disabled reporting when we're checking the stack for exception
frames. The behaviour isn't wrong, just incompatible with KASAN.
- Documentation!
- Dropped old module stuff in favour of KASAN_VMALLOC.
The bugs with ftrace and kuap were due to kernel bloat pushing
prom_init calls to be done via the plt. Because we did not have
a relocatable kernel, and they are done very early, this caused
everything to explode. Compile with CONFIG_RELOCATABLE!
---
Documentation/dev-tools/kasan.rst | 9 +-
Documentation/powerpc/kasan.txt | 112 ++++++++++++++++++-
arch/powerpc/Kconfig | 3 +-
arch/powerpc/Kconfig.debug | 23 +++-
arch/powerpc/Makefile | 11 ++
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 | 5 +
arch/powerpc/include/asm/kasan.h | 11 +-
arch/powerpc/kernel/Makefile | 2 +
arch/powerpc/kernel/process.c | 15 ++-
arch/powerpc/kernel/prom.c | 76 ++++++++++++-
arch/powerpc/mm/kasan/Makefile | 1 +
arch/powerpc/mm/kasan/init_book3s_64.c | 73 ++++++++++++
arch/powerpc/mm/ptdump/ptdump.c | 10 +-
arch/powerpc/platforms/Kconfig.cputype | 1 +
16 files changed, 345 insertions(+), 18 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 012ef3d91d1f..5722de91ccce 100644
--- a/Documentation/dev-tools/kasan.rst
+++ b/Documentation/dev-tools/kasan.rst
@@ -22,8 +22,9 @@ global variables yet.
Tag-based KASAN is only supported in Clang and requires version 7.0.0 or later.
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..bf645a5cd486 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 +10,113 @@ 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 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 in real mode after booting. Most notably a lot of KVM runs
+ in real mode, and it would be good to be able to instrument it.
+
+ - Because code runs in real mode after boot, the offset has to point to
+ valid memory both in and out of real mode.
+
+One approach is just to give up on inline instrumentation. This way all checks
+can be delayed until after everything set is up correctly, and the
+address-to-shadow calculations can be overridden. However, the features and
+speed boost provided by inline instrumentation are worth trying to do better.
+
+If _at compile time_ it is known how much contiguous physical memory a system
+has, the top 1/8th of the first block of physical memory can be set aside for
+the shadow. This is a big hammer and comes with 3 big consequences:
+
+ - there's no nice way to handle physically discontiguous memory, so only the
+ first physical memory block can be used.
+
+ - kernels will simply fail to boot on machines with less memory than specified
+ when compiling.
+
+ - kernels running on machines with more memory than specified when compiling
+ will simply ignore the extra memory.
+
+At the moment, this physical memory limit must be set _even for outline mode_.
+This may be changed in a future version - a different implementation could be
+added for outline mode that dynamically allocates shadow at a fixed offset.
+For example, see https://patchwork.ozlabs.org/patch/795211/
+
+This value is configured in CONFIG_PHYS_MEM_SIZE_FOR_KASAN.
+
+Tips
+----
+
+ - Compile with CONFIG_RELOCATABLE.
+
+ In development, boot hangs were observed when building with ftrace and KUAP
+ on. These ended up being due to kernel bloat pushing prom_init calls to be
+ done via the PLT. Because the kernel was not relocatable, and the calls are
+ done very early, this caused execution to jump off into somewhere
+ invalid. Enabling relocation fixes this.
+
+NUMA/discontiguous physical memory
+----------------------------------
+
+Currently the code cannot really deal with discontiguous physical memory. Only
+physical memory that is contiguous from physical address zero can be used. The
+size of that memory, not total memory, must be specified when configuring the
+kernel.
+
+Discontiguous memory can occur on machines with memory spread across multiple
+nodes. For example, on a Talos II with 64GB of RAM:
+
+ - 32GB runs from 0x0 to 0x0000_0008_0000_0000,
+ - then there's a gap,
+ - then the final 32GB runs from 0x0000_2000_0000_0000 to 0x0000_2008_0000_0000
+
+This can create _significant_ issues:
+
+ - If the machine is treated as having 64GB of _contiguous_ RAM, the
+ instrumentation would assume that it ran from 0x0 to
+ 0x0000_0010_0000_0000. The last 1/8th - 0x0000_000e_0000_0000 to
+ 0x0000_0010_0000_0000 would be reserved as the shadow region. But when the
+ kernel tried to access any of that, it would be trying to access pages that
+ are not physically present.
+
+ - If the shadow region size is based on the top address, then the shadow
+ region would be 0x2008_0000_0000 / 8 = 0x0401_0000_0000 bytes = 4100 GB of
+ memory, clearly more than the 64GB of RAM physically present.
+
+Therefore, the code currently is restricted to dealing with memory in the node
+starting at 0x0. For this system, that's 32GB. If a contiguous physical memory
+size greater than the size of the first contiguous region of memory is
+specified, the system will be unable to boot or even print an error message.
+
+The layout of a system's memory can be observed in the messages that the Radix
+MMU prints on boot. The Talos II discussed earlier has:
+
+radix-mmu: Mapped 0x0000000000000000-0x0000000040000000 with 1.00 GiB pages (exec)
+radix-mmu: Mapped 0x0000000040000000-0x0000000800000000 with 1.00 GiB pages
+radix-mmu: Mapped 0x0000200000000000-0x0000200800000000 with 1.00 GiB pages
+
+As discussed, this system would be configured for 32768 MB.
+
+Another system prints:
+
+radix-mmu: Mapped 0x0000000000000000-0x0000000040000000 with 1.00 GiB pages (exec)
+radix-mmu: Mapped 0x0000000040000000-0x0000002000000000 with 1.00 GiB pages
+radix-mmu: Mapped 0x0000200000000000-0x0000202000000000 with 1.00 GiB pages
+
+This machine has more memory: 0x0000_0040_0000_0000 total, but only
+0x0000_0020_0000_0000 is physically contiguous from zero, so it would be
+configured for 131072 MB of physically contiguous memory.
+
+This restriction currently also affects outline mode, but this could be
+changed in future if an alternative outline implementation is added.
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 497b7d0b2d7e..16f9c7205682 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -169,7 +169,8 @@ 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
- select HAVE_ARCH_KASAN_VMALLOC if PPC32
+ select HAVE_ARCH_KASAN 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 0b063830eea8..faed301a3b10 100644
--- a/arch/powerpc/Kconfig.debug
+++ b/arch/powerpc/Kconfig.debug
@@ -394,7 +394,28 @@ config PPC_FAST_ENDIAN_SWITCH
help
If you're unsure what this is, say N.
+config PHYS_MEM_SIZE_FOR_KASAN
+ int "Contiguous physical memory size for KASAN (MB)" if KASAN && PPC_BOOK3S_64
+ default 1024
+ help
+
+ To get inline instrumentation support for KASAN on 64-bit Book3S
+ machines, you need to know how much contiguous physical memory your
+ system has. A shadow offset will be calculated based on this figure,
+ which will be compiled in to the kernel. KASAN will use this offset
+ to access its shadow region, which is used to verify memory accesses.
+
+ If you attempt to boot on a system with less memory than you specify
+ here, your system will fail to boot very early in the process. If you
+ boot on a system with more memory than you specify, the extra memory
+ will wasted - it will be reserved and not used.
+
+ For systems with discontiguous blocks of physical memory, specify the
+ size of the block starting at 0x0. You can determine this by looking
+ at the memory layout info printed to dmesg by the radix MMU code
+ early in boot. See Documentation/powerpc/kasan.txt.
+
config KASAN_SHADOW_OFFSET
hex
- depends on KASAN
+ depends on KASAN && PPC32
default 0xe0000000
diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index cbe5ca4f0ee5..e075a0eac7a8 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -230,6 +230,17 @@ ifdef CONFIG_476FPE_ERR46
-T $(srctree)/arch/powerpc/platforms/44x/ppc476_modules.lds
endif
+ifdef CONFIG_PPC_BOOK3S_64
+# The KASAN shadow offset is such that linear map (0xc000...) is shadowed by
+# the last 8th of linearly mapped physical memory. This way, if the code uses
+# 0xc addresses throughout, accesses work both in in real mode (where the top
+# bits are ignored) and outside of real mode.
+#
+# 0xc000000000000000 >> 3 = 0xa800000000000000 = 12105675798371893248
+KASAN_SHADOW_OFFSET = $(shell echo 7 \* 1024 \* 1024 \* $(CONFIG_PHYS_MEM_SIZE_FOR_KASAN) / 8 + 12105675798371893248 | bc)
+KBUILD_CFLAGS += -DKASAN_SHADOW_OFFSET=$(KASAN_SHADOW_OFFSET)UL
+endif
+
# No AltiVec or VSX instructions when building kernel
KBUILD_CFLAGS += $(call cc-option,-mno-altivec)
KBUILD_CFLAGS += $(call cc-option,-mno-vsx)
diff --git a/arch/powerpc/include/asm/book3s/64/hash.h b/arch/powerpc/include/asm/book3s/64/hash.h
index 2781ebf6add4..fce329b8452e 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 201a69e6a355..309fb925a96e 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -231,6 +231,13 @@ 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 d97db3ad9aae..4f826259de71 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.
*/
diff --git a/arch/powerpc/include/asm/kasan.h b/arch/powerpc/include/asm/kasan.h
index fbff9ff9032e..b21d3ef88214 100644
--- a/arch/powerpc/include/asm/kasan.h
+++ b/arch/powerpc/include/asm/kasan.h
@@ -21,11 +21,18 @@
#define KASAN_SHADOW_START (KASAN_SHADOW_OFFSET + \
(PAGE_OFFSET >> 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 0UL
+#endif
-#define KASAN_SHADOW_SIZE (KASAN_SHADOW_END - KASAN_SHADOW_START)
+#ifdef CONFIG_PPC_BOOK3S_64
+#define KASAN_SHADOW_END (KASAN_SHADOW_OFFSET + \
+ (RADIX_VMEMMAP_END >> KASAN_SHADOW_SCALE_SHIFT))
+#endif
#ifdef CONFIG_KASAN
void kasan_early_init(void);
@@ -38,5 +45,5 @@ static inline void kasan_mmu_init(void) { }
static inline void kasan_late_init(void) { }
#endif
-#endif /* __ASSEMBLY */
+#endif /* !__ASSEMBLY__ */
#endif
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index 78a1b22d4fd8..079a3f37b0a0 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -34,6 +34,8 @@ 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
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 110db94cdf3c..e2c74a8e4464 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -2063,8 +2063,8 @@ 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("["REG"] ["REG"] %pS", sp, ip, (void *)ip);
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
@@ -2083,13 +2083,16 @@ 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("--- interrupt: %lx at %pS\n LR = %pS\n",
- regs->trap, (void *)regs->nip, (void *)lr);
+ READ_ONCE_NOCHECK(regs->trap),
+ (void *)READ_ONCE_NOCHECK(regs->nip),
+ (void *)READ_ONCE_NOCHECK(lr));
firstframe = 1;
}
diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index 6620f37abe73..a3ad2c661b49 100644
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -72,6 +72,7 @@ unsigned long tce_alloc_start, tce_alloc_end;
u64 ppc64_rma_size;
#endif
static phys_addr_t first_memblock_size;
+static phys_addr_t top_phys_addr;
static int __initdata boot_cpu_count;
static int __init early_parse_mem(char *p)
@@ -439,6 +440,36 @@ static int __init early_init_dt_scan_chosen_ppc(unsigned long node,
return 1;
}
+/*
+ * KASAN memory limit checking for 64-bit Book3S
+ *
+ * Currently we place the KASAN shadow region at the last 1/8th of the memory
+ * region that runs from 0 to CONFIG_PHYS_MEM_SIZE_FOR_KASAN.
+ *
+ * To handle the NUMA/discontiguous memory case, don't allow a block to be
+ * added if it falls completely beyond the configured physical memory. Print an
+ * informational message.
+ *
+ * Frustratingly we also see discontiguous memory with qemu - it seems to split
+ * the specified memory into a number of smaller blocks. If this happens under
+ * qemu, it probably represents misconfiguration. So we want the message to be
+ * noticeable, but not shouty.
+ *
+ * See Documentation/powerpc/kasan.txt
+ */
+
+static inline bool validate_kasan_mem_limit(u64 base, u64 size)
+{
+ if (IS_ENABLED(CONFIG_KASAN) && IS_ENABLED(CONFIG_PPC_BOOK3S_64) &&
+ (base >= ((u64)CONFIG_PHYS_MEM_SIZE_FOR_KASAN * SZ_1M))) {
+ pr_warn("KASAN: not adding memory block at %llx (size %llx)\n"
+ "This could be due to discontiguous memory or kernel misconfiguration.",
+ base, size);
+ return false;
+ }
+ return true;
+}
+
/*
* Compare the range against max mem limit and update
* size if it cross the limit.
@@ -449,6 +480,9 @@ static bool validate_mem_limit(u64 base, u64 *size)
{
u64 max_mem = 1UL << (MAX_PHYSMEM_BITS);
+ if (!validate_kasan_mem_limit(base, *size))
+ return false;
+
if (base >= max_mem)
return false;
if ((base + *size) > max_mem)
@@ -458,7 +492,7 @@ static bool validate_mem_limit(u64 base, u64 *size)
#else
static bool validate_mem_limit(u64 base, u64 *size)
{
- return true;
+ return validate_kasan_mem_limit(base, *size);
}
#endif
@@ -572,8 +606,10 @@ void __init early_init_dt_add_memory_arch(u64 base, u64 size)
/* Add the chunk to the MEMBLOCK list */
if (add_mem_to_memblock) {
- if (validate_mem_limit(base, &size))
+ if (validate_mem_limit(base, &size)) {
memblock_add(base, size);
+ top_phys_addr = max(top_phys_addr, (phys_addr_t)(base + size));
+ }
}
}
@@ -613,6 +649,8 @@ static void __init early_reserve_mem_dt(void)
static void __init early_reserve_mem(void)
{
__be64 *reserve_map;
+ phys_addr_t kasan_shadow_start;
+ phys_addr_t kasan_memory_size;
reserve_map = (__be64 *)(((unsigned long)initial_boot_params) +
fdt_off_mem_rsvmap(initial_boot_params));
@@ -651,6 +689,40 @@ static void __init early_reserve_mem(void)
return;
}
#endif
+
+ if (IS_ENABLED(CONFIG_KASAN) && IS_ENABLED(CONFIG_PPC_BOOK3S_64)) {
+ kasan_memory_size =
+ ((phys_addr_t)CONFIG_PHYS_MEM_SIZE_FOR_KASAN * SZ_1M);
+
+ if (top_phys_addr < kasan_memory_size) {
+ /*
+ * We are doomed. We shouldn't even be able to get this
+ * far, but we do in qemu. If we continue and turn
+ * relocations on, we'll take fatal page faults for
+ * memory that's not physically present. Instead,
+ * panic() here: it will be saved to __log_buf even if
+ * it doesn't get printed to the console.
+ */
+ panic("Tried to boot a KASAN kernel configured for %u MB with only %llu MB! Aborting.",
+ CONFIG_PHYS_MEM_SIZE_FOR_KASAN,
+ (u64)(top_phys_addr * SZ_1M));
+ } else if (top_phys_addr > kasan_memory_size) {
+ /* print a biiiig warning in hopes people notice */
+ pr_err("===========================================\n"
+ "Physical memory exceeds compiled-in maximum!\n"
+ "This kernel was compiled for KASAN with %u MB physical memory.\n"
+ "The physical memory detected is at least %llu MB.\n"
+ "Memory above the compiled limit will not be used!\n"
+ "===========================================\n",
+ CONFIG_PHYS_MEM_SIZE_FOR_KASAN,
+ (u64)(top_phys_addr / SZ_1M));
+ }
+
+ kasan_shadow_start = _ALIGN_DOWN(kasan_memory_size * 7 / 8, PAGE_SIZE);
+ DBG("reserving %llx -> %llx for KASAN",
+ kasan_shadow_start, top_phys_addr);
+ memblock_reserve(kasan_shadow_start, top_phys_addr - kasan_shadow_start);
+ }
}
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
diff --git a/arch/powerpc/mm/kasan/Makefile b/arch/powerpc/mm/kasan/Makefile
index 36a4e1b10b2d..f02b15c78e4d 100644
--- a/arch/powerpc/mm/kasan/Makefile
+++ b/arch/powerpc/mm/kasan/Makefile
@@ -3,3 +3,4 @@
KASAN_SANITIZE := n
obj-$(CONFIG_PPC32) += init_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..1c95fe6495c7
--- /dev/null
+++ b/arch/powerpc/mm/kasan/init_book3s_64.c
@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KASAN for 64-bit Book3S powerpc
+ *
+ * Copyright (C) 2019 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 <asm/pgalloc.h>
+
+void __init kasan_init(void)
+{
+ int i;
+ void *k_start = kasan_mem_to_shadow((void *)RADIX_KERN_VIRT_START);
+ void *k_end = kasan_mem_to_shadow((void *)RADIX_VMEMMAP_END);
+
+ pte_t pte = pte_mkpte(pfn_pte(virt_to_pfn(kasan_early_shadow_page),
+ PAGE_KERNEL));
+
+ if (!early_radix_enabled())
+ panic("KASAN requires radix!");
+
+ for (i = 0; i < PTRS_PER_PTE; i++)
+ __set_pte_at(&init_mm, (unsigned long)kasan_early_shadow_page,
+ &kasan_early_shadow_pte[i], 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);
+
+ memset((void *)KASAN_SHADOW_START, KASAN_SHADOW_INIT,
+ ((u64)CONFIG_PHYS_MEM_SIZE_FOR_KASAN *
+ SZ_1M >> KASAN_SHADOW_SCALE_SHIFT));
+
+ kasan_populate_early_shadow(kasan_mem_to_shadow((void *)RADIX_KERN_VIRT_START),
+ kasan_mem_to_shadow((void *)RADIX_VMALLOC_START));
+
+ /* leave a hole here for vmalloc */
+
+ kasan_populate_early_shadow(
+ kasan_mem_to_shadow((void *)RADIX_VMALLOC_END),
+ kasan_mem_to_shadow((void *)RADIX_VMEMMAP_END));
+
+ flush_tlb_kernel_range((unsigned long)k_start, (unsigned long)k_end);
+
+ /* mark early shadow region as RO and wipe */
+ pte = pte_mkpte(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], 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);
+
+ /* Enable error messages */
+ init_task.kasan_depth = 0;
+ pr_info("KASAN init done (64-bit Book3S heavyweight mode)\n");
+}
+
+void __init kasan_late_init(void) { }
diff --git a/arch/powerpc/mm/ptdump/ptdump.c b/arch/powerpc/mm/ptdump/ptdump.c
index d92bb8ea229c..dc95af39298c 100644
--- a/arch/powerpc/mm/ptdump/ptdump.c
+++ b/arch/powerpc/mm/ptdump/ptdump.c
@@ -73,6 +73,10 @@ struct addr_marker {
static struct addr_marker address_markers[] = {
{ 0, "Start of kernel VM" },
+#if defined(CONFIG_PPC64) && defined(CONFIG_KASAN)
+ { 0, "kasan shadow mem start" },
+ { 0, "kasan shadow mem end" },
+#endif
{ 0, "vmalloc() Area" },
{ 0, "vmalloc() End" },
#ifdef CONFIG_PPC64
@@ -92,10 +96,10 @@ static struct addr_marker address_markers[] = {
#endif
{ 0, "Fixmap start" },
{ 0, "Fixmap end" },
-#endif
#ifdef CONFIG_KASAN
{ 0, "kasan shadow mem start" },
{ 0, "kasan shadow mem end" },
+#endif
#endif
{ -1, NULL },
};
@@ -317,6 +321,10 @@ static void populate_markers(void)
int i = 0;
address_markers[i++].start_address = PAGE_OFFSET;
+#if defined(CONFIG_PPC64) && defined(CONFIG_KASAN)
+ address_markers[i++].start_address = KASAN_SHADOW_START;
+ address_markers[i++].start_address = KASAN_SHADOW_END;
+#endif
address_markers[i++].start_address = VMALLOC_START;
address_markers[i++].start_address = VMALLOC_END;
#ifdef CONFIG_PPC64
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index 4208724e9f28..1fc076db5cbc 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -99,6 +99,7 @@ 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"
--
2.20.1
^ permalink raw reply related
* [PATCH 0/4] powerpc/xive: fixes and debug extensions
From: Cédric Le Goater @ 2020-03-06 15:01 UTC (permalink / raw)
To: Michael Ellerman; +Cc: linuxppc-dev, Greg Kurz, Cédric Le Goater
Hello,
First two patches are fixes for non-critical issues. I checked that
they applied on stable.
Last two are debug extensions, one for xmon and the other to dump XIVE
internal state under debugfs, which is easier than xmon.
Cheers,
C.
Cédric Le Goater (4):
powerpc/xive: Use XIVE_BAD_IRQ instead of zero to catch non configured
IPIs
powerpc/xive: Fix xmon support on the PowerNV platform
powerpc/xmon: Add source flags to output of XIVE interrupts
powerpc/xive: Add a debugfs file to dump internal XIVE state
arch/powerpc/sysdev/xive/xive-internal.h | 9 ++
arch/powerpc/sysdev/xive/common.c | 126 +++++++++++++++++++++--
arch/powerpc/sysdev/xive/native.c | 7 +-
arch/powerpc/sysdev/xive/spapr.c | 23 ++++-
4 files changed, 151 insertions(+), 14 deletions(-)
--
2.21.1
^ permalink raw reply
* [PATCH] powerpc/kasan: Fix kasan_remap_early_shadow_ro()
From: Christophe Leroy @ 2020-03-06 15:09 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
At the moment kasan_remap_early_shadow_ro() does nothing, because
k_end is 0 and k_cur < 0 is always true.
Change the test to k_cur != k_end, as done in
kasan_init_shadow_page_tables()
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Fixes: cbd18991e24f ("powerpc/mm: Fix an Oops in kasan_mmu_init()")
Cc: stable@vger.kernel.org
---
arch/powerpc/mm/kasan/kasan_init_32.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/mm/kasan/kasan_init_32.c b/arch/powerpc/mm/kasan/kasan_init_32.c
index f19526e7d3dc..1a29cf469903 100644
--- a/arch/powerpc/mm/kasan/kasan_init_32.c
+++ b/arch/powerpc/mm/kasan/kasan_init_32.c
@@ -101,7 +101,7 @@ static void __init kasan_remap_early_shadow_ro(void)
kasan_populate_pte(kasan_early_shadow_pte, prot);
- for (k_cur = k_start & PAGE_MASK; k_cur < k_end; k_cur += PAGE_SIZE) {
+ for (k_cur = k_start & PAGE_MASK; k_cur != k_end; k_cur += PAGE_SIZE) {
pmd_t *pmd = pmd_ptr_k(k_cur);
pte_t *ptep = pte_offset_kernel(pmd, k_cur);
--
2.25.0
^ permalink raw reply related
* [PATCH v2] powerpc/kasan: Fix shadow memory protection with CONFIG_KASAN_VMALLOC
From: Christophe Leroy @ 2020-03-06 15:10 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
With CONFIG_KASAN_VMALLOC, new page tables are created at the time
shadow memory for vmalloc area in unmapped. If some parts of the
page table still has entries to the zero page shadow memory, the
entries are wrongly marked RW.
With CONFIG_KASAN_VMALLOC, almost the entire kernel address space
is managed by KASAN. To make it simple, just create KASAN page tables
for the entire kernel space at kasan_init(). That doesn't use much
more space, and that's anyway already done for hash platforms.
Fixes: 3d4247fcc938 ("powerpc/32: Add support of KASAN_VMALLOC")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
v2: Allocate all tables at init instead of doing it when
unmapping vmalloc space KASAN pages.
---
arch/powerpc/mm/kasan/kasan_init_32.c | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)
diff --git a/arch/powerpc/mm/kasan/kasan_init_32.c b/arch/powerpc/mm/kasan/kasan_init_32.c
index 1a29cf469903..c9174d645652 100644
--- a/arch/powerpc/mm/kasan/kasan_init_32.c
+++ b/arch/powerpc/mm/kasan/kasan_init_32.c
@@ -120,12 +120,6 @@ static void __init kasan_unmap_early_shadow_vmalloc(void)
unsigned long k_cur;
phys_addr_t pa = __pa(kasan_early_shadow_page);
- if (!early_mmu_has_feature(MMU_FTR_HPTE_TABLE)) {
- int ret = kasan_init_shadow_page_tables(k_start, k_end);
-
- if (ret)
- panic("kasan: kasan_init_shadow_page_tables() failed");
- }
for (k_cur = k_start & PAGE_MASK; k_cur < k_end; k_cur += PAGE_SIZE) {
pmd_t *pmd = pmd_offset(pud_offset(pgd_offset_k(k_cur), k_cur), k_cur);
pte_t *ptep = pte_offset_kernel(pmd, k_cur);
@@ -143,7 +137,7 @@ void __init kasan_mmu_init(void)
int ret;
struct memblock_region *reg;
- if (early_mmu_has_feature(MMU_FTR_HPTE_TABLE)) {
+ if (early_mmu_has_feature(MMU_FTR_HPTE_TABLE) || IS_ENABLED(CONFIG_KASAN_VMALLOC)) {
ret = kasan_init_shadow_page_tables(KASAN_SHADOW_START, KASAN_SHADOW_END);
if (ret)
--
2.25.0
^ permalink raw reply related
* [PATCH 1/4] powerpc/xive: Use XIVE_BAD_IRQ instead of zero to catch non configured IPIs
From: Cédric Le Goater @ 2020-03-06 15:01 UTC (permalink / raw)
To: Michael Ellerman
Cc: David Gibson, linuxppc-dev, Greg Kurz, stable,
Cédric Le Goater
In-Reply-To: <20200306150143.5551-1-clg@kaod.org>
When a CPU is brought up, an IPI number is allocated and recorded
under the XIVE CPU structure. Invalid IPI numbers are tracked with
interrupt number 0x0.
On the PowerNV platform, the interrupt number space starts at 0x10 and
this works fine. However, on the sPAPR platform, it is possible to
allocate the interrupt number 0x0 and this raises an issue when CPU 0
is unplugged. The XIVE spapr driver tracks allocated interrupt numbers
in a bitmask and it is not correctly updated when interrupt number 0x0
is freed. It stays allocated and it is then impossible to reallocate.
Fix by using the XIVE_BAD_IRQ value instead of zero on both platforms.
Reported-by: David Gibson <david@gibson.dropbear.id.au>
Fixes: eac1e731b59e ("powerpc/xive: guest exploitation of the XIVE interrupt controller")
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: Cédric Le Goater <clg@kaod.org>
---
arch/powerpc/sysdev/xive/xive-internal.h | 7 +++++++
arch/powerpc/sysdev/xive/common.c | 12 +++---------
arch/powerpc/sysdev/xive/native.c | 4 ++--
arch/powerpc/sysdev/xive/spapr.c | 4 ++--
4 files changed, 14 insertions(+), 13 deletions(-)
diff --git a/arch/powerpc/sysdev/xive/xive-internal.h b/arch/powerpc/sysdev/xive/xive-internal.h
index 59cd366e7933..382980f4de2d 100644
--- a/arch/powerpc/sysdev/xive/xive-internal.h
+++ b/arch/powerpc/sysdev/xive/xive-internal.h
@@ -5,6 +5,13 @@
#ifndef __XIVE_INTERNAL_H
#define __XIVE_INTERNAL_H
+/*
+ * A "disabled" interrupt should never fire, to catch problems
+ * we set its logical number to this
+ */
+#define XIVE_BAD_IRQ 0x7fffffff
+#define XIVE_MAX_IRQ (XIVE_BAD_IRQ - 1)
+
/* Each CPU carry one of these with various per-CPU state */
struct xive_cpu {
#ifdef CONFIG_SMP
diff --git a/arch/powerpc/sysdev/xive/common.c b/arch/powerpc/sysdev/xive/common.c
index fa49193206b6..550baba98ec9 100644
--- a/arch/powerpc/sysdev/xive/common.c
+++ b/arch/powerpc/sysdev/xive/common.c
@@ -68,13 +68,6 @@ static u32 xive_ipi_irq;
/* Xive state for each CPU */
static DEFINE_PER_CPU(struct xive_cpu *, xive_cpu);
-/*
- * A "disabled" interrupt should never fire, to catch problems
- * we set its logical number to this
- */
-#define XIVE_BAD_IRQ 0x7fffffff
-#define XIVE_MAX_IRQ (XIVE_BAD_IRQ - 1)
-
/* An invalid CPU target */
#define XIVE_INVALID_TARGET (-1)
@@ -1153,7 +1146,7 @@ static int xive_setup_cpu_ipi(unsigned int cpu)
xc = per_cpu(xive_cpu, cpu);
/* Check if we are already setup */
- if (xc->hw_ipi != 0)
+ if (xc->hw_ipi != XIVE_BAD_IRQ)
return 0;
/* Grab an IPI from the backend, this will populate xc->hw_ipi */
@@ -1190,7 +1183,7 @@ static void xive_cleanup_cpu_ipi(unsigned int cpu, struct xive_cpu *xc)
/* Disable the IPI and free the IRQ data */
/* Already cleaned up ? */
- if (xc->hw_ipi == 0)
+ if (xc->hw_ipi == XIVE_BAD_IRQ)
return;
/* Mask the IPI */
@@ -1346,6 +1339,7 @@ static int xive_prepare_cpu(unsigned int cpu)
if (np)
xc->chip_id = of_get_ibm_chip_id(np);
of_node_put(np);
+ xc->hw_ipi = XIVE_BAD_IRQ;
per_cpu(xive_cpu, cpu) = xc;
}
diff --git a/arch/powerpc/sysdev/xive/native.c b/arch/powerpc/sysdev/xive/native.c
index 0ff6b739052c..50e1a8e02497 100644
--- a/arch/powerpc/sysdev/xive/native.c
+++ b/arch/powerpc/sysdev/xive/native.c
@@ -312,7 +312,7 @@ static void xive_native_put_ipi(unsigned int cpu, struct xive_cpu *xc)
s64 rc;
/* Free the IPI */
- if (!xc->hw_ipi)
+ if (xc->hw_ipi == XIVE_BAD_IRQ)
return;
for (;;) {
rc = opal_xive_free_irq(xc->hw_ipi);
@@ -320,7 +320,7 @@ static void xive_native_put_ipi(unsigned int cpu, struct xive_cpu *xc)
msleep(OPAL_BUSY_DELAY_MS);
continue;
}
- xc->hw_ipi = 0;
+ xc->hw_ipi = XIVE_BAD_IRQ;
break;
}
}
diff --git a/arch/powerpc/sysdev/xive/spapr.c b/arch/powerpc/sysdev/xive/spapr.c
index 55dc61cb4867..3f15615712b5 100644
--- a/arch/powerpc/sysdev/xive/spapr.c
+++ b/arch/powerpc/sysdev/xive/spapr.c
@@ -560,11 +560,11 @@ static int xive_spapr_get_ipi(unsigned int cpu, struct xive_cpu *xc)
static void xive_spapr_put_ipi(unsigned int cpu, struct xive_cpu *xc)
{
- if (!xc->hw_ipi)
+ if (xc->hw_ipi == XIVE_BAD_IRQ)
return;
xive_irq_bitmap_free(xc->hw_ipi);
- xc->hw_ipi = 0;
+ xc->hw_ipi = XIVE_BAD_IRQ;
}
#endif /* CONFIG_SMP */
--
2.21.1
^ permalink raw reply related
* [PATCH 4/4] powerpc/xive: Add a debugfs file to dump internal XIVE state
From: Cédric Le Goater @ 2020-03-06 15:01 UTC (permalink / raw)
To: Michael Ellerman; +Cc: linuxppc-dev, Greg Kurz, Cédric Le Goater
In-Reply-To: <20200306150143.5551-1-clg@kaod.org>
As does XMON, the debugfs file /sys/kernel/debug/powerpc/xive exposes
the XIVE internal state of the machine CPUs and interrupts. Available
on the PowerNV and sPAPR platforms.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
---
arch/powerpc/sysdev/xive/xive-internal.h | 2 +
arch/powerpc/sysdev/xive/common.c | 105 +++++++++++++++++++++++
arch/powerpc/sysdev/xive/native.c | 3 +
arch/powerpc/sysdev/xive/spapr.c | 19 ++++
4 files changed, 129 insertions(+)
diff --git a/arch/powerpc/sysdev/xive/xive-internal.h b/arch/powerpc/sysdev/xive/xive-internal.h
index 382980f4de2d..b7b901da2168 100644
--- a/arch/powerpc/sysdev/xive/xive-internal.h
+++ b/arch/powerpc/sysdev/xive/xive-internal.h
@@ -57,12 +57,14 @@ struct xive_ops {
int (*get_ipi)(unsigned int cpu, struct xive_cpu *xc);
void (*put_ipi)(unsigned int cpu, struct xive_cpu *xc);
#endif
+ int (*debug_show)(struct seq_file *m, void *private);
const char *name;
};
bool xive_core_init(const struct xive_ops *ops, void __iomem *area, u32 offset,
u8 max_prio);
__be32 *xive_queue_page_alloc(unsigned int cpu, u32 queue_shift);
+int xive_core_debug_init(void);
static inline u32 xive_alloc_order(u32 queue_shift)
{
diff --git a/arch/powerpc/sysdev/xive/common.c b/arch/powerpc/sysdev/xive/common.c
index c865ae554605..e192077481a1 100644
--- a/arch/powerpc/sysdev/xive/common.c
+++ b/arch/powerpc/sysdev/xive/common.c
@@ -20,6 +20,7 @@
#include <linux/spinlock.h>
#include <linux/msi.h>
+#include <asm/debugfs.h>
#include <asm/prom.h>
#include <asm/io.h>
#include <asm/smp.h>
@@ -1558,3 +1559,107 @@ static int __init xive_off(char *arg)
return 0;
}
__setup("xive=off", xive_off);
+
+void xive_debug_show_cpu(struct seq_file *m, int cpu)
+{
+ struct xive_cpu *xc = per_cpu(xive_cpu, cpu);
+
+ seq_printf(m, "CPU %d:", cpu);
+ if (xc) {
+ seq_printf(m, "pp=%02x CPPR=%02x ", xc->pending_prio, xc->cppr);
+
+#ifdef CONFIG_SMP
+ {
+ u64 val = xive_esb_read(&xc->ipi_data, XIVE_ESB_GET);
+
+ seq_printf(m, "IPI=0x%08x PQ=%c%c ", xc->hw_ipi,
+ val & XIVE_ESB_VAL_P ? 'P' : '-',
+ val & XIVE_ESB_VAL_Q ? 'Q' : '-');
+ }
+#endif
+ {
+ struct xive_q *q = &xc->queue[xive_irq_priority];
+ u32 i0, i1, idx;
+
+ if (q->qpage) {
+ idx = q->idx;
+ i0 = be32_to_cpup(q->qpage + idx);
+ idx = (idx + 1) & q->msk;
+ i1 = be32_to_cpup(q->qpage + idx);
+ seq_printf(m, "EQ idx=%d T=%d %08x %08x ...",
+ q->idx, q->toggle, i0, i1);
+ }
+ }
+ }
+ seq_puts(m, "\n");
+}
+
+void xive_debug_show_irq(struct seq_file *m, u32 hw_irq, struct irq_data *d)
+{
+ struct irq_chip *chip = irq_data_get_irq_chip(d);
+ int rc;
+ u32 target;
+ u8 prio;
+ u32 lirq;
+
+ if (!is_xive_irq(chip))
+ return;
+
+ rc = xive_ops->get_irq_config(hw_irq, &target, &prio, &lirq);
+ if (rc) {
+ seq_printf(m, "IRQ 0x%08x : no config rc=%d\n", hw_irq, rc);
+ return;
+ }
+
+ seq_printf(m, "IRQ 0x%08x : target=0x%x prio=%02x lirq=0x%x ",
+ hw_irq, target, prio, lirq);
+
+ if (d) {
+ struct xive_irq_data *xd = irq_data_get_irq_handler_data(d);
+ u64 val = xive_esb_read(xd, XIVE_ESB_GET);
+
+ seq_printf(m, "flags=%c%c%c PQ=%c%c",
+ xd->flags & XIVE_IRQ_FLAG_STORE_EOI ? 'S' : ' ',
+ xd->flags & XIVE_IRQ_FLAG_LSI ? 'L' : ' ',
+ xd->flags & XIVE_IRQ_FLAG_H_INT_ESB ? 'H' : ' ',
+ val & XIVE_ESB_VAL_P ? 'P' : '-',
+ val & XIVE_ESB_VAL_Q ? 'Q' : '-');
+ }
+ seq_puts(m, "\n");
+}
+
+static int xive_core_debug_show(struct seq_file *m, void *private)
+{
+ unsigned int i;
+ struct irq_desc *desc;
+ int cpu;
+
+ if (xive_ops->debug_show)
+ xive_ops->debug_show(m, private);
+
+ for_each_possible_cpu(cpu)
+ xive_debug_show_cpu(m, cpu);
+
+ for_each_irq_desc(i, desc) {
+ struct irq_data *d = irq_desc_get_irq_data(desc);
+ unsigned int hw_irq;
+
+ if (!d)
+ continue;
+
+ hw_irq = (unsigned int)irqd_to_hwirq(d);
+
+ /* IPIs are special (HW number 0) */
+ if (hw_irq)
+ xive_debug_show_irq(m, hw_irq, d);
+ }
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(xive_core_debug);
+
+int xive_core_debug_init(void)
+{
+ debugfs_create_file("xive", 0444, powerpc_debugfs_root,
+ NULL, &xive_core_debug_fops);
+ return 0;
+}
diff --git a/arch/powerpc/sysdev/xive/native.c b/arch/powerpc/sysdev/xive/native.c
index 50e1a8e02497..5218fdc4b29a 100644
--- a/arch/powerpc/sysdev/xive/native.c
+++ b/arch/powerpc/sysdev/xive/native.c
@@ -19,6 +19,7 @@
#include <linux/cpumask.h>
#include <linux/mm.h>
+#include <asm/machdep.h>
#include <asm/prom.h>
#include <asm/io.h>
#include <asm/smp.h>
@@ -850,3 +851,5 @@ int xive_native_get_vp_state(u32 vp_id, u64 *out_state)
return 0;
}
EXPORT_SYMBOL_GPL(xive_native_get_vp_state);
+
+machine_arch_initcall(powernv, xive_core_debug_init);
diff --git a/arch/powerpc/sysdev/xive/spapr.c b/arch/powerpc/sysdev/xive/spapr.c
index 3f15615712b5..7ab5c6780997 100644
--- a/arch/powerpc/sysdev/xive/spapr.c
+++ b/arch/powerpc/sysdev/xive/spapr.c
@@ -18,6 +18,7 @@
#include <linux/delay.h>
#include <linux/libfdt.h>
+#include <asm/machdep.h>
#include <asm/prom.h>
#include <asm/io.h>
#include <asm/smp.h>
@@ -645,6 +646,21 @@ static void xive_spapr_sync_source(u32 hw_irq)
plpar_int_sync(0, hw_irq);
}
+static int xive_spapr_debug_show(struct seq_file *m, void *private)
+{
+ struct xive_irq_bitmap *xibm;
+ char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+
+ list_for_each_entry(xibm, &xive_irq_bitmaps, list) {
+ memset(buf, 0, PAGE_SIZE);
+ bitmap_print_to_pagebuf(true, buf, xibm->bitmap, xibm->count);
+ seq_printf(m, "bitmap #%d: %s", xibm->count, buf);
+ }
+ kfree(buf);
+
+ return 0;
+}
+
static const struct xive_ops xive_spapr_ops = {
.populate_irq_data = xive_spapr_populate_irq_data,
.configure_irq = xive_spapr_configure_irq,
@@ -662,6 +678,7 @@ static const struct xive_ops xive_spapr_ops = {
#ifdef CONFIG_SMP
.get_ipi = xive_spapr_get_ipi,
.put_ipi = xive_spapr_put_ipi,
+ .debug_show = xive_spapr_debug_show,
#endif /* CONFIG_SMP */
.name = "spapr",
};
@@ -839,3 +856,5 @@ bool __init xive_spapr_init(void)
pr_info("Using %dkB queues\n", 1 << (xive_queue_shift - 10));
return true;
}
+
+machine_arch_initcall(pseries, xive_core_debug_init);
--
2.21.1
^ permalink raw reply related
* [PATCH v3] powerpc/kasan: Fix shadow memory protection with CONFIG_KASAN_VMALLOC
From: Christophe Leroy @ 2020-03-06 16:49 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
With CONFIG_KASAN_VMALLOC, new page tables are created at the time
shadow memory for vmalloc area in unmapped. If some parts of the
page table still has entries to the zero page shadow memory, the
entries are wrongly marked RW.
With CONFIG_KASAN_VMALLOC, almost the entire kernel address space
is managed by KASAN. To make it simple, just create KASAN page tables
for the entire kernel space at kasan_init(). That doesn't use much
more space, and that's anyway already done for hash platforms.
Fixes: 3d4247fcc938 ("powerpc/32: Add support of KASAN_VMALLOC")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
v3: Split a too long line
v2: Allocate all tables at init instead of doing it when
unmapping vmalloc space KASAN pages.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
arch/powerpc/mm/kasan/kasan_init_32.c | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/mm/kasan/kasan_init_32.c b/arch/powerpc/mm/kasan/kasan_init_32.c
index 1a29cf469903..cbcad369fcb2 100644
--- a/arch/powerpc/mm/kasan/kasan_init_32.c
+++ b/arch/powerpc/mm/kasan/kasan_init_32.c
@@ -120,12 +120,6 @@ static void __init kasan_unmap_early_shadow_vmalloc(void)
unsigned long k_cur;
phys_addr_t pa = __pa(kasan_early_shadow_page);
- if (!early_mmu_has_feature(MMU_FTR_HPTE_TABLE)) {
- int ret = kasan_init_shadow_page_tables(k_start, k_end);
-
- if (ret)
- panic("kasan: kasan_init_shadow_page_tables() failed");
- }
for (k_cur = k_start & PAGE_MASK; k_cur < k_end; k_cur += PAGE_SIZE) {
pmd_t *pmd = pmd_offset(pud_offset(pgd_offset_k(k_cur), k_cur), k_cur);
pte_t *ptep = pte_offset_kernel(pmd, k_cur);
@@ -143,7 +137,8 @@ void __init kasan_mmu_init(void)
int ret;
struct memblock_region *reg;
- if (early_mmu_has_feature(MMU_FTR_HPTE_TABLE)) {
+ if (early_mmu_has_feature(MMU_FTR_HPTE_TABLE) ||
+ IS_ENABLED(CONFIG_KASAN_VMALLOC)) {
ret = kasan_init_shadow_page_tables(KASAN_SHADOW_START, KASAN_SHADOW_END);
if (ret)
--
2.25.0
^ permalink raw reply related
* Re: [PATCH v2 4/5] powerpc/sysfs: Show idle_purr and idle_spurr for every CPU
From: Nathan Lynch @ 2020-03-06 17:03 UTC (permalink / raw)
To: Naveen N. Rao
Cc: Tyrel Datwyler, ego, linux-kernel, Kamalesh Babulal,
Vaidyanathan Srinivasan, linuxppc-dev
In-Reply-To: <1582625516.nbsanohdks.naveen@linux.ibm.com>
"Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> writes:
> Gautham R Shenoy wrote:
>> On Fri, Feb 21, 2020 at 10:50:12AM -0600, Nathan Lynch wrote:
>>> It's regrettable that we have to wake up potentially idle CPUs in order
>>> to derive correct idle statistics for them, but I suppose the main user
>>> (lparstat) of these interfaces already is causing this to happen by
>>> polling the existing per-cpu purr and spurr attributes.
>>>
>>> So now lparstat will incur at minimum four syscalls and four IPIs per
>>> CPU per polling interval -- one for each of purr, spurr, idle_purr and
>>> idle_spurr. Correct?
>>
>> Yes, it is unforunate that we will end up making four syscalls and
>> generating IPI noise, and this is something that I discussed with
>> Naveen and Kamalesh. We have the following two constraints:
>>
>> 1) These values of PURR and SPURR required are per-cpu. Hence putting
>> them in lparcfg is not an option.
>>
>> 2) sysfs semantics encourages a single value per key, the key being
>> the sysfs-file. Something like the following would have made far more
>> sense.
>>
>> cat /sys/devices/system/cpu/cpuX/purr_spurr_accounting
>> purr:A
>> idle_purr:B
>> spurr:C
>> idle_spurr:D
>>
>> There are some sysfs files which allow something like this. Eg:
>> /sys/devices/system/cpu/cpu0/cpufreq/stats/time_in_state
>>
>> Thoughts on any other alternatives?
>
> Umm... procfs?
> /me ducks
I had wondered about perf events but I'm not sure that's any more suitable.
>>> At some point it's going to make sense to batch sampling of remote CPUs'
>>> SPRs.
>
> How did you mean this? It looks like we first need to provide a separate
> user interface, since with the existing sysfs interface providing
> separate files, I am not sure if we can batch such reads.
I mean in order to minimize IPI traffic something like: sample/calculate
all of a CPU's purr, idle_purr, spurr, idle_spurr in a single IPI upon a
read of any of the attributes, and cache the result for some time, so
that the anticipated subsequent reads of the other attributes use the
cached results instead of generating more IPIs.
That would keep the current sysfs interface at the cost of imposing a
certain coarseness in the results.
Anyway, that's a mitigation that could be considered if the
implementation in this patch is found to be too expensive in practice.
^ permalink raw reply
* Re: [PATCH v2 1/5] powerpc: Move idle_loop_prolog()/epilog() functions to header file
From: Nathan Lynch @ 2020-03-06 17:06 UTC (permalink / raw)
To: Gautham R Shenoy
Cc: Tyrel Datwyler, linux-kernel, Kamalesh Babulal, Naveen N. Rao,
Vaidyanathan Srinivasan, linuxppc-dev
In-Reply-To: <20200224045506.GA12846@in.ibm.com>
Gautham R Shenoy <ego@linux.vnet.ibm.com> writes:
> On Fri, Feb 21, 2020 at 09:03:16AM -0600, Nathan Lynch wrote:
>> Looks fine and correct as a cleanup, but asm/include/idle.h and
>> idle_loop_prolog, idle_loop_epilog, strike me as too generic for
>> pseries-specific code.
>
> Should it be prefixed with pseries , i.e pseries_idle_prolog()
> and pseries_idle_epilog() ?
Yes that seems appropriate to me.
^ permalink raw reply
* [PATCH v4 0/7] Allow setting caching mode in arch_add_memory() for P2PDMA
From: Logan Gunthorpe @ 2020-03-06 17:08 UTC (permalink / raw)
To: linux-kernel, linux-arm-kernel, linux-ia64, linuxppc-dev,
linux-s390, linux-sh, platform-driver-x86, linux-mm, Dan Williams,
Michal Hocko, David Hildenbrand, Andrew Morton
Cc: Eric Badger, Peter Zijlstra, Catalin Marinas, Dave Hansen,
Logan Gunthorpe, Ingo Molnar, Borislav Petkov, Andy Lutomirski,
Thomas Gleixner, Will Deacon, Christoph Hellwig
Hi,
This is v4 of the patchset which cleans up a number of minor issues
from the feedback of v3 and rebases onto v5.6-rc4. Additional feedback
is welcome.
Also worth noting, is that the kernel test robot reports[1] that Patch 3
in this series improves will-it-scale.per_process_ops by 36%. Though,
for the life of me, I can't understand why that would be. But it's
reported the same thing twice now for different versions of the series.
Thanks,
Logan
[1] https://lists.01.org/hyperkitty/list/lkp@lists.01.org/thread/5APDKNBEJGVJTJRTI2IIA3P4OC2OEYPS/
--
Changes in v4:
* Rebased onto v5.6-rc4
* Collected tags form David, Dan and Michal
* Minor changes to the new _set_memory_prot() function and added some
comments as requested by Dan.
* Changed the default caching type for P2PDMA memory to UC instead of
WC per Jason's concerns that WC might be more generally unsafe.
Changes in v3:
* Rebased onto v5.6-rc2
* Rename mhp_modifiers to mhp_params per David with an updated kernel
doc per Dan
* Drop support for s390 per David seeing it does not support
ZONE_DEVICE yet and there was a potential problem with huge pages.
* Added WARN_ON_ONCE in cases where arches recieve non PAGE_KERNEL
parameters
* Collected David and Micheal's Reviewed-By and Acked-by Tags
Changes in v2:
* Rebased onto v5.5-rc5
* Renamed mhp_restrictions to mhp_modifiers and added the pgprot field
to that structure instead of using an argument for
arch_add_memory().
* Add patch to drop the unused flags field in mhp_restrictions
A git branch is available here:
https://github.com/sbates130272/linux-p2pmem remap_pages_cache_v4
--
Currently, the page tables created using memremap_pages() are always
created with the PAGE_KERNEL cacheing mode. However, the P2PDMA code
is creating pages for PCI BAR memory which should never be accessed
through the cache and instead use either WC or UC. This still works in
most cases, on x86, because the MTRR registers typically override the
caching settings in the page tables for all of the IO memory to be
UC-. However, this tends not to work so well on other arches or
some rare x86 machines that have firmware which does not setup the
MTRR registers in this way.
Instead of this, this series proposes a change to arch_add_memory()
to take the pgprot required by the mapping which allows us to
explicitly set pagetable entries for P2PDMA memory to UC.
This changes is pretty routine for most of the arches: x86_64, arm64
and powerpc simply need to thread the pgprot through to where the page
tables are setup. x86_32 unfortunately sets up the page tables at boot so
must use _set_memory_prot() to change their caching mode. ia64, s390 and sh
don't appear to have an easy way to change the page tables so, for now
at least, we just return -EINVAL on such mappings and thus they will
not support P2PDMA memory until the work for this is done. This should
be fine as they don't yet support ZONE_DEVICE.
--
Logan Gunthorpe (7):
mm/memory_hotplug: Drop the flags field from struct mhp_restrictions
mm/memory_hotplug: Rename mhp_restrictions to mhp_params
x86/mm: Thread pgprot_t through init_memory_mapping()
x86/mm: Introduce __set_memory_prot()
powerpc/mm: Thread pgprot_t through create_section_mapping()
mm/memory_hotplug: Add pgprot_t to mhp_params
mm/memremap: Set caching mode for PCI P2PDMA memory to WC
arch/arm64/mm/mmu.c | 7 ++--
arch/ia64/mm/init.c | 7 ++--
arch/powerpc/include/asm/book3s/64/hash.h | 3 +-
arch/powerpc/include/asm/book3s/64/radix.h | 3 +-
arch/powerpc/include/asm/sparsemem.h | 3 +-
arch/powerpc/mm/book3s64/hash_utils.c | 5 +--
arch/powerpc/mm/book3s64/pgtable.c | 7 ++--
arch/powerpc/mm/book3s64/radix_pgtable.c | 18 ++++++----
arch/powerpc/mm/mem.c | 10 +++---
arch/s390/mm/init.c | 9 +++--
arch/sh/mm/init.c | 7 ++--
arch/x86/include/asm/page_types.h | 3 --
arch/x86/include/asm/pgtable.h | 3 ++
arch/x86/include/asm/set_memory.h | 1 +
arch/x86/kernel/amd_gart_64.c | 3 +-
arch/x86/mm/init.c | 9 ++---
arch/x86/mm/init_32.c | 19 ++++++++--
arch/x86/mm/init_64.c | 40 ++++++++++++----------
arch/x86/mm/mm_internal.h | 3 +-
arch/x86/mm/pat/set_memory.c | 13 +++++++
arch/x86/platform/uv/bios_uv.c | 3 +-
include/linux/memory_hotplug.h | 21 ++++++------
mm/memory_hotplug.c | 11 +++---
mm/memremap.c | 17 +++++----
24 files changed, 144 insertions(+), 81 deletions(-)
base-commit: 98d54f81e36ba3bf92172791eba5ca5bd813989b
--
2.20.1
^ permalink raw reply
* [PATCH v4 1/7] mm/memory_hotplug: Drop the flags field from struct mhp_restrictions
From: Logan Gunthorpe @ 2020-03-06 17:08 UTC (permalink / raw)
To: linux-kernel, linux-arm-kernel, linux-ia64, linuxppc-dev,
linux-s390, linux-sh, platform-driver-x86, linux-mm, Dan Williams,
Michal Hocko, David Hildenbrand, Andrew Morton
Cc: Eric Badger, Peter Zijlstra, Catalin Marinas, Dave Hansen,
Michal Hocko, Logan Gunthorpe, Ingo Molnar, Borislav Petkov,
Andy Lutomirski, Thomas Gleixner, Will Deacon, Christoph Hellwig
In-Reply-To: <20200306170846.9333-1-logang@deltatee.com>
This variable is not used anywhere and should therefore be removed
from the structure.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
---
include/linux/memory_hotplug.h | 2 --
1 file changed, 2 deletions(-)
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index f4d59155f3d4..69ff3037528d 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -55,11 +55,9 @@ enum {
/*
* Restrictions for the memory hotplug:
- * flags: MHP_ flags
* altmap: alternative allocator for memmap array
*/
struct mhp_restrictions {
- unsigned long flags;
struct vmem_altmap *altmap;
};
--
2.20.1
^ permalink raw reply related
* [PATCH v4 3/7] x86/mm: Thread pgprot_t through init_memory_mapping()
From: Logan Gunthorpe @ 2020-03-06 17:08 UTC (permalink / raw)
To: linux-kernel, linux-arm-kernel, linux-ia64, linuxppc-dev,
linux-s390, linux-sh, platform-driver-x86, linux-mm, Dan Williams,
Michal Hocko, David Hildenbrand, Andrew Morton
Cc: Eric Badger, H. Peter Anvin, Peter Zijlstra, Catalin Marinas,
Dave Hansen, Michal Hocko, x86, Logan Gunthorpe, Ingo Molnar,
Borislav Petkov, Andy Lutomirski, Thomas Gleixner, Will Deacon,
Christoph Hellwig
In-Reply-To: <20200306170846.9333-1-logang@deltatee.com>
In prepartion to support a pgprot_t argument for arch_add_memory().
It's required to move the prototype of init_memory_mapping() seeing
the original location came before the definition of pgprot_t.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
---
arch/x86/include/asm/page_types.h | 3 ---
arch/x86/include/asm/pgtable.h | 3 +++
arch/x86/kernel/amd_gart_64.c | 3 ++-
arch/x86/mm/init.c | 9 +++++----
arch/x86/mm/init_32.c | 3 ++-
arch/x86/mm/init_64.c | 32 +++++++++++++++++--------------
arch/x86/mm/mm_internal.h | 3 ++-
arch/x86/platform/uv/bios_uv.c | 3 ++-
8 files changed, 34 insertions(+), 25 deletions(-)
diff --git a/arch/x86/include/asm/page_types.h b/arch/x86/include/asm/page_types.h
index c85e15010f48..bf7aa2e290ef 100644
--- a/arch/x86/include/asm/page_types.h
+++ b/arch/x86/include/asm/page_types.h
@@ -73,9 +73,6 @@ static inline phys_addr_t get_max_mapped(void)
bool pfn_range_is_mapped(unsigned long start_pfn, unsigned long end_pfn);
-extern unsigned long init_memory_mapping(unsigned long start,
- unsigned long end);
-
extern void initmem_init(void);
#endif /* !__ASSEMBLY__ */
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index 7e118660bbd9..48d6a5960f28 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -1046,6 +1046,9 @@ static inline void __meminit init_trampoline_default(void)
void __init poking_init(void);
+unsigned long init_memory_mapping(unsigned long start,
+ unsigned long end, pgprot_t prot);
+
# ifdef CONFIG_RANDOMIZE_MEMORY
void __meminit init_trampoline(void);
# else
diff --git a/arch/x86/kernel/amd_gart_64.c b/arch/x86/kernel/amd_gart_64.c
index 4e5f50236048..16133819415c 100644
--- a/arch/x86/kernel/amd_gart_64.c
+++ b/arch/x86/kernel/amd_gart_64.c
@@ -744,7 +744,8 @@ int __init gart_iommu_init(void)
start_pfn = PFN_DOWN(aper_base);
if (!pfn_range_is_mapped(start_pfn, end_pfn))
- init_memory_mapping(start_pfn<<PAGE_SHIFT, end_pfn<<PAGE_SHIFT);
+ init_memory_mapping(start_pfn<<PAGE_SHIFT, end_pfn<<PAGE_SHIFT,
+ PAGE_KERNEL);
pr_info("PCI-DMA: using GART IOMMU.\n");
iommu_size = check_iommu_size(info.aper_base, aper_size);
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index e7bb483557c9..1bba16c5742b 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -467,7 +467,7 @@ bool pfn_range_is_mapped(unsigned long start_pfn, unsigned long end_pfn)
* the physical memory. To access them they are temporarily mapped.
*/
unsigned long __ref init_memory_mapping(unsigned long start,
- unsigned long end)
+ unsigned long end, pgprot_t prot)
{
struct map_range mr[NR_RANGE_MR];
unsigned long ret = 0;
@@ -481,7 +481,8 @@ unsigned long __ref init_memory_mapping(unsigned long start,
for (i = 0; i < nr_range; i++)
ret = kernel_physical_mapping_init(mr[i].start, mr[i].end,
- mr[i].page_size_mask);
+ mr[i].page_size_mask,
+ prot);
add_pfn_range_mapped(start >> PAGE_SHIFT, ret >> PAGE_SHIFT);
@@ -521,7 +522,7 @@ static unsigned long __init init_range_memory_mapping(
*/
can_use_brk_pgt = max(start, (u64)pgt_buf_end<<PAGE_SHIFT) >=
min(end, (u64)pgt_buf_top<<PAGE_SHIFT);
- init_memory_mapping(start, end);
+ init_memory_mapping(start, end, PAGE_KERNEL);
mapped_ram_size += end - start;
can_use_brk_pgt = true;
}
@@ -661,7 +662,7 @@ void __init init_mem_mapping(void)
#endif
/* the ISA range is always mapped regardless of memory holes */
- init_memory_mapping(0, ISA_END_ADDRESS);
+ init_memory_mapping(0, ISA_END_ADDRESS, PAGE_KERNEL);
/* Init the trampoline, possibly with KASLR memory offset */
init_trampoline();
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 3ec3dac7c268..e25a4218e6ff 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -253,7 +253,8 @@ static inline int is_kernel_text(unsigned long addr)
unsigned long __init
kernel_physical_mapping_init(unsigned long start,
unsigned long end,
- unsigned long page_size_mask)
+ unsigned long page_size_mask,
+ pgprot_t prot)
{
int use_pse = page_size_mask == (1<<PG_LEVEL_2M);
unsigned long last_map_addr = end;
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 87977a8bfbbf..9e7692080dda 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -585,7 +585,7 @@ phys_pmd_init(pmd_t *pmd_page, unsigned long paddr, unsigned long paddr_end,
*/
static unsigned long __meminit
phys_pud_init(pud_t *pud_page, unsigned long paddr, unsigned long paddr_end,
- unsigned long page_size_mask, bool init)
+ unsigned long page_size_mask, pgprot_t _prot, bool init)
{
unsigned long pages = 0, paddr_next;
unsigned long paddr_last = paddr_end;
@@ -595,7 +595,7 @@ phys_pud_init(pud_t *pud_page, unsigned long paddr, unsigned long paddr_end,
for (; i < PTRS_PER_PUD; i++, paddr = paddr_next) {
pud_t *pud;
pmd_t *pmd;
- pgprot_t prot = PAGE_KERNEL;
+ pgprot_t prot = _prot;
vaddr = (unsigned long)__va(paddr);
pud = pud_page + pud_index(vaddr);
@@ -644,9 +644,12 @@ phys_pud_init(pud_t *pud_page, unsigned long paddr, unsigned long paddr_end,
if (page_size_mask & (1<<PG_LEVEL_1G)) {
pages++;
spin_lock(&init_mm.page_table_lock);
+
+ prot = __pgprot(pgprot_val(prot) | __PAGE_KERNEL_LARGE);
+
set_pte_init((pte_t *)pud,
pfn_pte((paddr & PUD_MASK) >> PAGE_SHIFT,
- PAGE_KERNEL_LARGE),
+ prot),
init);
spin_unlock(&init_mm.page_table_lock);
paddr_last = paddr_next;
@@ -669,7 +672,7 @@ phys_pud_init(pud_t *pud_page, unsigned long paddr, unsigned long paddr_end,
static unsigned long __meminit
phys_p4d_init(p4d_t *p4d_page, unsigned long paddr, unsigned long paddr_end,
- unsigned long page_size_mask, bool init)
+ unsigned long page_size_mask, pgprot_t prot, bool init)
{
unsigned long vaddr, vaddr_end, vaddr_next, paddr_next, paddr_last;
@@ -679,7 +682,7 @@ phys_p4d_init(p4d_t *p4d_page, unsigned long paddr, unsigned long paddr_end,
if (!pgtable_l5_enabled())
return phys_pud_init((pud_t *) p4d_page, paddr, paddr_end,
- page_size_mask, init);
+ page_size_mask, prot, init);
for (; vaddr < vaddr_end; vaddr = vaddr_next) {
p4d_t *p4d = p4d_page + p4d_index(vaddr);
@@ -702,13 +705,13 @@ phys_p4d_init(p4d_t *p4d_page, unsigned long paddr, unsigned long paddr_end,
if (!p4d_none(*p4d)) {
pud = pud_offset(p4d, 0);
paddr_last = phys_pud_init(pud, paddr, __pa(vaddr_end),
- page_size_mask, init);
+ page_size_mask, prot, init);
continue;
}
pud = alloc_low_page();
paddr_last = phys_pud_init(pud, paddr, __pa(vaddr_end),
- page_size_mask, init);
+ page_size_mask, prot, init);
spin_lock(&init_mm.page_table_lock);
p4d_populate_init(&init_mm, p4d, pud, init);
@@ -722,7 +725,7 @@ static unsigned long __meminit
__kernel_physical_mapping_init(unsigned long paddr_start,
unsigned long paddr_end,
unsigned long page_size_mask,
- bool init)
+ pgprot_t prot, bool init)
{
bool pgd_changed = false;
unsigned long vaddr, vaddr_start, vaddr_end, vaddr_next, paddr_last;
@@ -743,13 +746,13 @@ __kernel_physical_mapping_init(unsigned long paddr_start,
paddr_last = phys_p4d_init(p4d, __pa(vaddr),
__pa(vaddr_end),
page_size_mask,
- init);
+ prot, init);
continue;
}
p4d = alloc_low_page();
paddr_last = phys_p4d_init(p4d, __pa(vaddr), __pa(vaddr_end),
- page_size_mask, init);
+ page_size_mask, prot, init);
spin_lock(&init_mm.page_table_lock);
if (pgtable_l5_enabled())
@@ -778,10 +781,10 @@ __kernel_physical_mapping_init(unsigned long paddr_start,
unsigned long __meminit
kernel_physical_mapping_init(unsigned long paddr_start,
unsigned long paddr_end,
- unsigned long page_size_mask)
+ unsigned long page_size_mask, pgprot_t prot)
{
return __kernel_physical_mapping_init(paddr_start, paddr_end,
- page_size_mask, true);
+ page_size_mask, prot, true);
}
/*
@@ -796,7 +799,8 @@ kernel_physical_mapping_change(unsigned long paddr_start,
unsigned long page_size_mask)
{
return __kernel_physical_mapping_init(paddr_start, paddr_end,
- page_size_mask, false);
+ page_size_mask, PAGE_KERNEL,
+ false);
}
#ifndef CONFIG_NUMA
@@ -864,7 +868,7 @@ int arch_add_memory(int nid, u64 start, u64 size,
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
- init_memory_mapping(start, start + size);
+ init_memory_mapping(start, start + size, PAGE_KERNEL);
return add_pages(nid, start_pfn, nr_pages, params);
}
diff --git a/arch/x86/mm/mm_internal.h b/arch/x86/mm/mm_internal.h
index eeae142062ed..3f37b5c80bb3 100644
--- a/arch/x86/mm/mm_internal.h
+++ b/arch/x86/mm/mm_internal.h
@@ -12,7 +12,8 @@ void early_ioremap_page_table_range_init(void);
unsigned long kernel_physical_mapping_init(unsigned long start,
unsigned long end,
- unsigned long page_size_mask);
+ unsigned long page_size_mask,
+ pgprot_t prot);
unsigned long kernel_physical_mapping_change(unsigned long start,
unsigned long end,
unsigned long page_size_mask);
diff --git a/arch/x86/platform/uv/bios_uv.c b/arch/x86/platform/uv/bios_uv.c
index 607f58147311..c60255da5a6c 100644
--- a/arch/x86/platform/uv/bios_uv.c
+++ b/arch/x86/platform/uv/bios_uv.c
@@ -352,7 +352,8 @@ void __iomem *__init efi_ioremap(unsigned long phys_addr, unsigned long size,
if (type == EFI_MEMORY_MAPPED_IO)
return ioremap(phys_addr, size);
- last_map_pfn = init_memory_mapping(phys_addr, phys_addr + size);
+ last_map_pfn = init_memory_mapping(phys_addr, phys_addr + size,
+ PAGE_KERNEL);
if ((last_map_pfn << PAGE_SHIFT) < phys_addr + size) {
unsigned long top = last_map_pfn << PAGE_SHIFT;
efi_ioremap(top, size - (top - phys_addr), type, attribute);
--
2.20.1
^ permalink raw reply related
* [PATCH v4 5/7] powerpc/mm: Thread pgprot_t through create_section_mapping()
From: Logan Gunthorpe @ 2020-03-06 17:08 UTC (permalink / raw)
To: linux-kernel, linux-arm-kernel, linux-ia64, linuxppc-dev,
linux-s390, linux-sh, platform-driver-x86, linux-mm, Dan Williams,
Michal Hocko, David Hildenbrand, Andrew Morton
Cc: Eric Badger, Peter Zijlstra, Catalin Marinas, Dave Hansen,
Logan Gunthorpe, Ingo Molnar, Borislav Petkov, Andy Lutomirski,
Paul Mackerras, Thomas Gleixner, Will Deacon, Christoph Hellwig
In-Reply-To: <20200306170846.9333-1-logang@deltatee.com>
In prepartion to support a pgprot_t argument for arch_add_memory().
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
---
arch/powerpc/include/asm/book3s/64/hash.h | 3 ++-
arch/powerpc/include/asm/book3s/64/radix.h | 3 ++-
arch/powerpc/include/asm/sparsemem.h | 3 ++-
arch/powerpc/mm/book3s64/hash_utils.c | 5 +++--
arch/powerpc/mm/book3s64/pgtable.c | 7 ++++---
arch/powerpc/mm/book3s64/radix_pgtable.c | 18 +++++++++++-------
arch/powerpc/mm/mem.c | 5 +++--
7 files changed, 27 insertions(+), 17 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/hash.h b/arch/powerpc/include/asm/book3s/64/hash.h
index 2781ebf6add4..6fc4520092c7 100644
--- a/arch/powerpc/include/asm/book3s/64/hash.h
+++ b/arch/powerpc/include/asm/book3s/64/hash.h
@@ -251,7 +251,8 @@ extern int __meminit hash__vmemmap_create_mapping(unsigned long start,
extern void hash__vmemmap_remove_mapping(unsigned long start,
unsigned long page_size);
-int hash__create_section_mapping(unsigned long start, unsigned long end, int nid);
+int hash__create_section_mapping(unsigned long start, unsigned long end,
+ int nid, pgprot_t prot);
int hash__remove_section_mapping(unsigned long start, unsigned long end);
#endif /* !__ASSEMBLY__ */
diff --git a/arch/powerpc/include/asm/book3s/64/radix.h b/arch/powerpc/include/asm/book3s/64/radix.h
index d97db3ad9aae..46799f3c3d1d 100644
--- a/arch/powerpc/include/asm/book3s/64/radix.h
+++ b/arch/powerpc/include/asm/book3s/64/radix.h
@@ -289,7 +289,8 @@ static inline unsigned long radix__get_tree_size(void)
}
#ifdef CONFIG_MEMORY_HOTPLUG
-int radix__create_section_mapping(unsigned long start, unsigned long end, int nid);
+int radix__create_section_mapping(unsigned long start, unsigned long end,
+ int nid, pgprot_t prot);
int radix__remove_section_mapping(unsigned long start, unsigned long end);
#endif /* CONFIG_MEMORY_HOTPLUG */
#endif /* __ASSEMBLY__ */
diff --git a/arch/powerpc/include/asm/sparsemem.h b/arch/powerpc/include/asm/sparsemem.h
index 3192d454a733..c89b32443cff 100644
--- a/arch/powerpc/include/asm/sparsemem.h
+++ b/arch/powerpc/include/asm/sparsemem.h
@@ -13,7 +13,8 @@
#endif /* CONFIG_SPARSEMEM */
#ifdef CONFIG_MEMORY_HOTPLUG
-extern int create_section_mapping(unsigned long start, unsigned long end, int nid);
+extern int create_section_mapping(unsigned long start, unsigned long end,
+ int nid, pgprot_t prot);
extern int remove_section_mapping(unsigned long start, unsigned long end);
#ifdef CONFIG_PPC_BOOK3S_64
diff --git a/arch/powerpc/mm/book3s64/hash_utils.c b/arch/powerpc/mm/book3s64/hash_utils.c
index 523d4d39d11e..201738e07a1d 100644
--- a/arch/powerpc/mm/book3s64/hash_utils.c
+++ b/arch/powerpc/mm/book3s64/hash_utils.c
@@ -809,7 +809,8 @@ int resize_hpt_for_hotplug(unsigned long new_mem_size)
return 0;
}
-int hash__create_section_mapping(unsigned long start, unsigned long end, int nid)
+int hash__create_section_mapping(unsigned long start, unsigned long end,
+ int nid, pgprot_t prot)
{
int rc;
@@ -819,7 +820,7 @@ int hash__create_section_mapping(unsigned long start, unsigned long end, int nid
}
rc = htab_bolt_mapping(start, end, __pa(start),
- pgprot_val(PAGE_KERNEL), mmu_linear_psize,
+ pgprot_val(prot), mmu_linear_psize,
mmu_kernel_ssize);
if (rc < 0) {
diff --git a/arch/powerpc/mm/book3s64/pgtable.c b/arch/powerpc/mm/book3s64/pgtable.c
index 2bf7e1b4fd82..e0bb69c616e4 100644
--- a/arch/powerpc/mm/book3s64/pgtable.c
+++ b/arch/powerpc/mm/book3s64/pgtable.c
@@ -171,12 +171,13 @@ void mmu_cleanup_all(void)
}
#ifdef CONFIG_MEMORY_HOTPLUG
-int __meminit create_section_mapping(unsigned long start, unsigned long end, int nid)
+int __meminit create_section_mapping(unsigned long start, unsigned long end,
+ int nid, pgprot_t prot)
{
if (radix_enabled())
- return radix__create_section_mapping(start, end, nid);
+ return radix__create_section_mapping(start, end, nid, prot);
- return hash__create_section_mapping(start, end, nid);
+ return hash__create_section_mapping(start, end, nid, prot);
}
int __meminit remove_section_mapping(unsigned long start, unsigned long end)
diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
index dd1bea45325c..0ef10b5c26ba 100644
--- a/arch/powerpc/mm/book3s64/radix_pgtable.c
+++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -253,7 +253,7 @@ static unsigned long next_boundary(unsigned long addr, unsigned long end)
static int __meminit create_physical_mapping(unsigned long start,
unsigned long end,
- int nid)
+ int nid, pgprot_t _prot)
{
unsigned long vaddr, addr, mapping_size = 0;
bool prev_exec, exec = false;
@@ -289,7 +289,7 @@ static int __meminit create_physical_mapping(unsigned long start,
prot = PAGE_KERNEL_X;
exec = true;
} else {
- prot = PAGE_KERNEL;
+ prot = _prot;
exec = false;
}
@@ -333,7 +333,7 @@ static void __init radix_init_pgtable(void)
WARN_ON(create_physical_mapping(reg->base,
reg->base + reg->size,
- -1));
+ -1, PAGE_KERNEL));
}
/* Find out how many PID bits are supported */
@@ -712,8 +712,10 @@ static int __meminit stop_machine_change_mapping(void *data)
spin_unlock(&init_mm.page_table_lock);
pte_clear(&init_mm, params->aligned_start, params->pte);
- create_physical_mapping(__pa(params->aligned_start), __pa(params->start), -1);
- create_physical_mapping(__pa(params->end), __pa(params->aligned_end), -1);
+ create_physical_mapping(__pa(params->aligned_start),
+ __pa(params->start), -1, PAGE_KERNEL);
+ create_physical_mapping(__pa(params->end), __pa(params->aligned_end),
+ -1, PAGE_KERNEL);
spin_lock(&init_mm.page_table_lock);
return 0;
}
@@ -870,14 +872,16 @@ static void __meminit remove_pagetable(unsigned long start, unsigned long end)
radix__flush_tlb_kernel_range(start, end);
}
-int __meminit radix__create_section_mapping(unsigned long start, unsigned long end, int nid)
+int __meminit radix__create_section_mapping(unsigned long start,
+ unsigned long end, int nid,
+ pgprot_t prot)
{
if (end >= RADIX_VMALLOC_START) {
pr_warn("Outside the supported range\n");
return -1;
}
- return create_physical_mapping(__pa(start), __pa(end), nid);
+ return create_physical_mapping(__pa(start), __pa(end), nid, prot);
}
int __meminit radix__remove_section_mapping(unsigned long start, unsigned long end)
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index b4bece53bec0..19b1da5d7eca 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -96,7 +96,8 @@ int memory_add_physaddr_to_nid(u64 start)
}
#endif
-int __weak create_section_mapping(unsigned long start, unsigned long end, int nid)
+int __weak create_section_mapping(unsigned long start, unsigned long end,
+ int nid, pgprot_t prot)
{
return -ENODEV;
}
@@ -137,7 +138,7 @@ int __ref arch_add_memory(int nid, u64 start, u64 size,
resize_hpt_for_hotplug(memblock_phys_mem_size());
start = (unsigned long)__va(start);
- rc = create_section_mapping(start, start + size, nid);
+ rc = create_section_mapping(start, start + size, nid, PAGE_KERNEL);
if (rc) {
pr_warn("Unable to create mapping for hot added memory 0x%llx..0x%llx: %d\n",
start, start + size, rc);
--
2.20.1
^ permalink raw reply related
* [PATCH v4 4/7] x86/mm: Introduce __set_memory_prot()
From: Logan Gunthorpe @ 2020-03-06 17:08 UTC (permalink / raw)
To: linux-kernel, linux-arm-kernel, linux-ia64, linuxppc-dev,
linux-s390, linux-sh, platform-driver-x86, linux-mm, Dan Williams,
Michal Hocko, David Hildenbrand, Andrew Morton
Cc: Eric Badger, H. Peter Anvin, Peter Zijlstra, Catalin Marinas,
Dave Hansen, x86, Logan Gunthorpe, Ingo Molnar, Borislav Petkov,
Andy Lutomirski, Thomas Gleixner, Will Deacon, Christoph Hellwig
In-Reply-To: <20200306170846.9333-1-logang@deltatee.com>
For use in the 32bit arch_add_memory() to set the pgprot type of the
memory to add.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
---
arch/x86/include/asm/set_memory.h | 1 +
arch/x86/mm/pat/set_memory.c | 13 +++++++++++++
2 files changed, 14 insertions(+)
diff --git a/arch/x86/include/asm/set_memory.h b/arch/x86/include/asm/set_memory.h
index 64c3dce374e5..034358da4837 100644
--- a/arch/x86/include/asm/set_memory.h
+++ b/arch/x86/include/asm/set_memory.h
@@ -34,6 +34,7 @@
* The caller is required to take care of these.
*/
+int __set_memory_prot(unsigned long addr, int numpages, pgprot_t prot);
int _set_memory_uc(unsigned long addr, int numpages);
int _set_memory_wc(unsigned long addr, int numpages);
int _set_memory_wt(unsigned long addr, int numpages);
diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c
index c4aedd00c1ba..a7b14dffeb0b 100644
--- a/arch/x86/mm/pat/set_memory.c
+++ b/arch/x86/mm/pat/set_memory.c
@@ -1792,6 +1792,19 @@ static inline int cpa_clear_pages_array(struct page **pages, int numpages,
CPA_PAGES_ARRAY, pages);
}
+/*
+ * _set_memory_prot is an internal helper for callers that have been passed
+ * a pgprot_t value from upper layers and a reservation has already been taken.
+ * If you want to set the pgprot to a specific page protocol, use the
+ * set_memory_xx() functions.
+ */
+int __set_memory_prot(unsigned long addr, int numpages, pgprot_t prot)
+{
+ return change_page_attr_set_clr(&addr, numpages, prot,
+ __pgprot(~pgprot_val(prot)), 0, 0,
+ NULL);
+}
+
int _set_memory_uc(unsigned long addr, int numpages)
{
/*
--
2.20.1
^ permalink raw reply related
* [PATCH v4 6/7] mm/memory_hotplug: Add pgprot_t to mhp_params
From: Logan Gunthorpe @ 2020-03-06 17:08 UTC (permalink / raw)
To: linux-kernel, linux-arm-kernel, linux-ia64, linuxppc-dev,
linux-s390, linux-sh, platform-driver-x86, linux-mm, Dan Williams,
Michal Hocko, David Hildenbrand, Andrew Morton
Cc: Eric Badger, Peter Zijlstra, Catalin Marinas, Dave Hansen,
Michal Hocko, Logan Gunthorpe, Ingo Molnar, Borislav Petkov,
Andy Lutomirski, Thomas Gleixner, Will Deacon, Christoph Hellwig
In-Reply-To: <20200306170846.9333-1-logang@deltatee.com>
devm_memremap_pages() is currently used by the PCI P2PDMA code to create
struct page mappings for IO memory. At present, these mappings are created
with PAGE_KERNEL which implies setting the PAT bits to be WB. However, on
x86, an mtrr register will typically override this and force the cache
type to be UC-. In the case firmware doesn't set this register it is
effectively WB and will typically result in a machine check exception
when it's accessed.
Other arches are not currently likely to function correctly seeing they
don't have any MTRR registers to fall back on.
To solve this, provide a way to specify the pgprot value explicitly to
arch_add_memory().
Of the arches that support MEMORY_HOTPLUG: x86_64, and arm64 need a simple
change to pass the pgprot_t down to their respective functions which set
up the page tables. For x86_32, set the page tables explicitly using
_set_memory_prot() (seeing they are already mapped). For ia64, s390 and
sh, reject anything but PAGE_KERNEL settings -- this should be fine,
for now, seeing these architectures don't support ZONE_DEVICE.
A check in __add_pages() is also added to ensure the pgprot parameter was
set for all arches.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
---
arch/arm64/mm/mmu.c | 3 ++-
arch/ia64/mm/init.c | 3 +++
arch/powerpc/mm/mem.c | 3 ++-
arch/s390/mm/init.c | 3 +++
arch/sh/mm/init.c | 3 +++
arch/x86/mm/init_32.c | 12 ++++++++++++
arch/x86/mm/init_64.c | 2 +-
include/linux/memory_hotplug.h | 3 +++
mm/memory_hotplug.c | 5 ++++-
mm/memremap.c | 6 +++---
10 files changed, 36 insertions(+), 7 deletions(-)
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index ee37bca8aba8..ea3fa844a8a2 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -1058,7 +1058,8 @@ int arch_add_memory(int nid, u64 start, u64 size,
flags = NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS;
__create_pgd_mapping(swapper_pg_dir, start, __phys_to_virt(start),
- size, PAGE_KERNEL, __pgd_pgtable_alloc, flags);
+ size, params->pgprot, __pgd_pgtable_alloc,
+ flags);
memblock_clear_nomap(start, size);
diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c
index 97bbc23ea1e3..d637b4ea3147 100644
--- a/arch/ia64/mm/init.c
+++ b/arch/ia64/mm/init.c
@@ -676,6 +676,9 @@ int arch_add_memory(int nid, u64 start, u64 size,
unsigned long nr_pages = size >> PAGE_SHIFT;
int ret;
+ if (WARN_ON_ONCE(params->pgprot.pgprot != PAGE_KERNEL.pgprot))
+ return -EINVAL;
+
ret = __add_pages(nid, start_pfn, nr_pages, params);
if (ret)
printk("%s: Problem encountered in __add_pages() as ret=%d\n",
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 19b1da5d7eca..832412bc7fad 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -138,7 +138,8 @@ int __ref arch_add_memory(int nid, u64 start, u64 size,
resize_hpt_for_hotplug(memblock_phys_mem_size());
start = (unsigned long)__va(start);
- rc = create_section_mapping(start, start + size, nid, PAGE_KERNEL);
+ rc = create_section_mapping(start, start + size, nid,
+ params->pgprot);
if (rc) {
pr_warn("Unable to create mapping for hot added memory 0x%llx..0x%llx: %d\n",
start, start + size, rc);
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index e9e4a7abd0cc..87b2d024e75a 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -277,6 +277,9 @@ int arch_add_memory(int nid, u64 start, u64 size,
if (WARN_ON_ONCE(params->altmap))
return -EINVAL;
+ if (WARN_ON_ONCE(params->pgprot.pgprot != PAGE_KERNEL.pgprot))
+ return -EINVAL;
+
rc = vmem_add_mapping(start, size);
if (rc)
return rc;
diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
index e5114c053364..b9de2d4fa57e 100644
--- a/arch/sh/mm/init.c
+++ b/arch/sh/mm/init.c
@@ -412,6 +412,9 @@ int arch_add_memory(int nid, u64 start, u64 size,
unsigned long nr_pages = size >> PAGE_SHIFT;
int ret;
+ if (WARN_ON_ONCE(params->pgprot.pgprot != PAGE_KERNEL.pgprot)
+ return -EINVAL;
+
/* We only have ZONE_NORMAL, so this is easy.. */
ret = __add_pages(nid, start_pfn, nr_pages, params);
if (unlikely(ret))
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index e25a4218e6ff..69128f1a22ac 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -858,6 +858,18 @@ int arch_add_memory(int nid, u64 start, u64 size,
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
+ int ret;
+
+ /*
+ * The page tables were already mapped at boot so if the caller
+ * requests a different mapping type then we must change all the
+ * pages with __set_memory_prot().
+ */
+ if (params->pgprot.pgprot != PAGE_KERNEL.pgprot) {
+ ret = __set_memory_prot(start, nr_pages, params->pgprot);
+ if (ret)
+ return ret;
+ }
return __add_pages(nid, start_pfn, nr_pages, params);
}
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 9e7692080dda..230240af38b4 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -868,7 +868,7 @@ int arch_add_memory(int nid, u64 start, u64 size,
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
- init_memory_mapping(start, start + size, PAGE_KERNEL);
+ init_memory_mapping(start, start + size, params->pgprot);
return add_pages(nid, start_pfn, nr_pages, params);
}
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index c5df1b3dada0..3195d11876ea 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -56,9 +56,12 @@ enum {
/*
* Extended parameters for memory hotplug:
* altmap: alternative allocator for memmap array (optional)
+ * pgprot: page protection flags to apply to newly created page tables
+ * (required)
*/
struct mhp_params {
struct vmem_altmap *altmap;
+ pgprot_t pgprot;
};
/*
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index c69469e1b40e..d7d4806ad81b 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -305,6 +305,9 @@ int __ref __add_pages(int nid, unsigned long pfn, unsigned long nr_pages,
unsigned long nr, start_sec, end_sec;
struct vmem_altmap *altmap = params->altmap;
+ if (WARN_ON_ONCE(!params->pgprot.pgprot))
+ return -EINVAL;
+
err = check_hotplug_memory_addressable(pfn, nr_pages);
if (err)
return err;
@@ -993,7 +996,7 @@ static int online_memory_block(struct memory_block *mem, void *arg)
*/
int __ref add_memory_resource(int nid, struct resource *res)
{
- struct mhp_params params = {};
+ struct mhp_params params = { .pgprot = PAGE_KERNEL };
u64 start, size;
bool new_node = false;
int ret;
diff --git a/mm/memremap.c b/mm/memremap.c
index 6891a503a078..06742372a203 100644
--- a/mm/memremap.c
+++ b/mm/memremap.c
@@ -166,8 +166,8 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid)
* We do not want any optional features only our own memmap
*/
.altmap = pgmap_altmap(pgmap),
+ .pgprot = PAGE_KERNEL,
};
- pgprot_t pgprot = PAGE_KERNEL;
int error, is_ram;
bool need_devmap_managed = true;
@@ -255,8 +255,8 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid)
if (nid < 0)
nid = numa_mem_id();
- error = track_pfn_remap(NULL, &pgprot, PHYS_PFN(res->start), 0,
- resource_size(res));
+ error = track_pfn_remap(NULL, ¶ms.pgprot, PHYS_PFN(res->start),
+ 0, resource_size(res));
if (error)
goto err_pfn_remap;
--
2.20.1
^ permalink raw reply related
* [PATCH v4 2/7] mm/memory_hotplug: Rename mhp_restrictions to mhp_params
From: Logan Gunthorpe @ 2020-03-06 17:08 UTC (permalink / raw)
To: linux-kernel, linux-arm-kernel, linux-ia64, linuxppc-dev,
linux-s390, linux-sh, platform-driver-x86, linux-mm, Dan Williams,
Michal Hocko, David Hildenbrand, Andrew Morton
Cc: Eric Badger, Peter Zijlstra, Catalin Marinas, Dave Hansen,
Michal Hocko, Logan Gunthorpe, Ingo Molnar, Borislav Petkov,
Andy Lutomirski, Thomas Gleixner, Will Deacon, Christoph Hellwig
In-Reply-To: <20200306170846.9333-1-logang@deltatee.com>
The mhp_restrictions struct really doesn't specify anything resembling
a restriction anymore so rename it to be mhp_params as it is a list
of extended parameters.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
---
arch/arm64/mm/mmu.c | 4 ++--
arch/ia64/mm/init.c | 4 ++--
arch/powerpc/mm/mem.c | 4 ++--
arch/s390/mm/init.c | 6 +++---
arch/sh/mm/init.c | 4 ++--
arch/x86/mm/init_32.c | 4 ++--
arch/x86/mm/init_64.c | 8 ++++----
include/linux/memory_hotplug.h | 16 ++++++++--------
mm/memory_hotplug.c | 8 ++++----
mm/memremap.c | 8 ++++----
10 files changed, 33 insertions(+), 33 deletions(-)
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 128f70852bf3..ee37bca8aba8 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -1050,7 +1050,7 @@ int p4d_free_pud_page(p4d_t *p4d, unsigned long addr)
#ifdef CONFIG_MEMORY_HOTPLUG
int arch_add_memory(int nid, u64 start, u64 size,
- struct mhp_restrictions *restrictions)
+ struct mhp_params *params)
{
int flags = 0;
@@ -1063,7 +1063,7 @@ int arch_add_memory(int nid, u64 start, u64 size,
memblock_clear_nomap(start, size);
return __add_pages(nid, start >> PAGE_SHIFT, size >> PAGE_SHIFT,
- restrictions);
+ params);
}
void arch_remove_memory(int nid, u64 start, u64 size,
struct vmem_altmap *altmap)
diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c
index b01d68a2d5d9..97bbc23ea1e3 100644
--- a/arch/ia64/mm/init.c
+++ b/arch/ia64/mm/init.c
@@ -670,13 +670,13 @@ mem_init (void)
#ifdef CONFIG_MEMORY_HOTPLUG
int arch_add_memory(int nid, u64 start, u64 size,
- struct mhp_restrictions *restrictions)
+ struct mhp_params *params)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
int ret;
- ret = __add_pages(nid, start_pfn, nr_pages, restrictions);
+ ret = __add_pages(nid, start_pfn, nr_pages, params);
if (ret)
printk("%s: Problem encountered in __add_pages() as ret=%d\n",
__func__, ret);
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index ef7b1119b2e2..b4bece53bec0 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -128,7 +128,7 @@ static void flush_dcache_range_chunked(unsigned long start, unsigned long stop,
}
int __ref arch_add_memory(int nid, u64 start, u64 size,
- struct mhp_restrictions *restrictions)
+ struct mhp_params *params)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
@@ -144,7 +144,7 @@ int __ref arch_add_memory(int nid, u64 start, u64 size,
return -EFAULT;
}
- return __add_pages(nid, start_pfn, nr_pages, restrictions);
+ return __add_pages(nid, start_pfn, nr_pages, params);
}
void __ref arch_remove_memory(int nid, u64 start, u64 size,
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index ac44bd76db4b..e9e4a7abd0cc 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -268,20 +268,20 @@ device_initcall(s390_cma_mem_init);
#endif /* CONFIG_CMA */
int arch_add_memory(int nid, u64 start, u64 size,
- struct mhp_restrictions *restrictions)
+ struct mhp_params *params)
{
unsigned long start_pfn = PFN_DOWN(start);
unsigned long size_pages = PFN_DOWN(size);
int rc;
- if (WARN_ON_ONCE(restrictions->altmap))
+ if (WARN_ON_ONCE(params->altmap))
return -EINVAL;
rc = vmem_add_mapping(start, size);
if (rc)
return rc;
- rc = __add_pages(nid, start_pfn, size_pages, restrictions);
+ rc = __add_pages(nid, start_pfn, size_pages, params);
if (rc)
vmem_remove_mapping(start, size);
return rc;
diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
index d1b1ff2be17a..e5114c053364 100644
--- a/arch/sh/mm/init.c
+++ b/arch/sh/mm/init.c
@@ -406,14 +406,14 @@ void __init mem_init(void)
#ifdef CONFIG_MEMORY_HOTPLUG
int arch_add_memory(int nid, u64 start, u64 size,
- struct mhp_restrictions *restrictions)
+ struct mhp_params *params)
{
unsigned long start_pfn = PFN_DOWN(start);
unsigned long nr_pages = size >> PAGE_SHIFT;
int ret;
/* We only have ZONE_NORMAL, so this is easy.. */
- ret = __add_pages(nid, start_pfn, nr_pages, restrictions);
+ ret = __add_pages(nid, start_pfn, nr_pages, params);
if (unlikely(ret))
printk("%s: Failed, __add_pages() == %d\n", __func__, ret);
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 23df4885bbed..3ec3dac7c268 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -853,12 +853,12 @@ void __init mem_init(void)
#ifdef CONFIG_MEMORY_HOTPLUG
int arch_add_memory(int nid, u64 start, u64 size,
- struct mhp_restrictions *restrictions)
+ struct mhp_params *params)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
- return __add_pages(nid, start_pfn, nr_pages, restrictions);
+ return __add_pages(nid, start_pfn, nr_pages, params);
}
void arch_remove_memory(int nid, u64 start, u64 size,
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index abbdecb75fad..87977a8bfbbf 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -844,11 +844,11 @@ static void update_end_of_memory_vars(u64 start, u64 size)
}
int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
- struct mhp_restrictions *restrictions)
+ struct mhp_params *params)
{
int ret;
- ret = __add_pages(nid, start_pfn, nr_pages, restrictions);
+ ret = __add_pages(nid, start_pfn, nr_pages, params);
WARN_ON_ONCE(ret);
/* update max_pfn, max_low_pfn and high_memory */
@@ -859,14 +859,14 @@ int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
}
int arch_add_memory(int nid, u64 start, u64 size,
- struct mhp_restrictions *restrictions)
+ struct mhp_params *params)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
init_memory_mapping(start, start + size);
- return add_pages(nid, start_pfn, nr_pages, restrictions);
+ return add_pages(nid, start_pfn, nr_pages, params);
}
#define PAGE_INUSE 0xFD
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index 69ff3037528d..c5df1b3dada0 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -54,10 +54,10 @@ enum {
};
/*
- * Restrictions for the memory hotplug:
- * altmap: alternative allocator for memmap array
+ * Extended parameters for memory hotplug:
+ * altmap: alternative allocator for memmap array (optional)
*/
-struct mhp_restrictions {
+struct mhp_params {
struct vmem_altmap *altmap;
};
@@ -108,7 +108,7 @@ extern int restore_online_page_callback(online_page_callback_t callback);
extern int try_online_node(int nid);
extern int arch_add_memory(int nid, u64 start, u64 size,
- struct mhp_restrictions *restrictions);
+ struct mhp_params *params);
extern u64 max_mem_size;
extern bool memhp_auto_online;
@@ -126,17 +126,17 @@ extern void __remove_pages(unsigned long start_pfn, unsigned long nr_pages,
/* reasonably generic interface to expand the physical pages */
extern int __add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
- struct mhp_restrictions *restrictions);
+ struct mhp_params *params);
#ifndef CONFIG_ARCH_HAS_ADD_PAGES
static inline int add_pages(int nid, unsigned long start_pfn,
- unsigned long nr_pages, struct mhp_restrictions *restrictions)
+ unsigned long nr_pages, struct mhp_params *params)
{
- return __add_pages(nid, start_pfn, nr_pages, restrictions);
+ return __add_pages(nid, start_pfn, nr_pages, params);
}
#else /* ARCH_HAS_ADD_PAGES */
int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
- struct mhp_restrictions *restrictions);
+ struct mhp_params *params);
#endif /* ARCH_HAS_ADD_PAGES */
#ifdef CONFIG_NUMA
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 0a54ffac8c68..c69469e1b40e 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -299,11 +299,11 @@ static int check_hotplug_memory_addressable(unsigned long pfn,
* add the new pages.
*/
int __ref __add_pages(int nid, unsigned long pfn, unsigned long nr_pages,
- struct mhp_restrictions *restrictions)
+ struct mhp_params *params)
{
int err;
unsigned long nr, start_sec, end_sec;
- struct vmem_altmap *altmap = restrictions->altmap;
+ struct vmem_altmap *altmap = params->altmap;
err = check_hotplug_memory_addressable(pfn, nr_pages);
if (err)
@@ -993,7 +993,7 @@ static int online_memory_block(struct memory_block *mem, void *arg)
*/
int __ref add_memory_resource(int nid, struct resource *res)
{
- struct mhp_restrictions restrictions = {};
+ struct mhp_params params = {};
u64 start, size;
bool new_node = false;
int ret;
@@ -1021,7 +1021,7 @@ int __ref add_memory_resource(int nid, struct resource *res)
new_node = ret;
/* call arch's memory hotadd */
- ret = arch_add_memory(nid, start, size, &restrictions);
+ ret = arch_add_memory(nid, start, size, ¶ms);
if (ret < 0)
goto error;
diff --git a/mm/memremap.c b/mm/memremap.c
index 09b5b7adc773..6891a503a078 100644
--- a/mm/memremap.c
+++ b/mm/memremap.c
@@ -161,7 +161,7 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid)
{
struct resource *res = &pgmap->res;
struct dev_pagemap *conflict_pgmap;
- struct mhp_restrictions restrictions = {
+ struct mhp_params params = {
/*
* We do not want any optional features only our own memmap
*/
@@ -275,7 +275,7 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid)
*/
if (pgmap->type == MEMORY_DEVICE_PRIVATE) {
error = add_pages(nid, PHYS_PFN(res->start),
- PHYS_PFN(resource_size(res)), &restrictions);
+ PHYS_PFN(resource_size(res)), ¶ms);
} else {
error = kasan_add_zero_shadow(__va(res->start), resource_size(res));
if (error) {
@@ -284,7 +284,7 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid)
}
error = arch_add_memory(nid, res->start, resource_size(res),
- &restrictions);
+ ¶ms);
}
if (!error) {
@@ -292,7 +292,7 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid)
zone = &NODE_DATA(nid)->node_zones[ZONE_DEVICE];
move_pfn_range_to_zone(zone, PHYS_PFN(res->start),
- PHYS_PFN(resource_size(res)), restrictions.altmap);
+ PHYS_PFN(resource_size(res)), params.altmap);
}
mem_hotplug_done();
--
2.20.1
^ permalink raw reply related
* [PATCH v4 7/7] mm/memremap: Set caching mode for PCI P2PDMA memory to WC
From: Logan Gunthorpe @ 2020-03-06 17:08 UTC (permalink / raw)
To: linux-kernel, linux-arm-kernel, linux-ia64, linuxppc-dev,
linux-s390, linux-sh, platform-driver-x86, linux-mm, Dan Williams,
Michal Hocko, David Hildenbrand, Andrew Morton
Cc: Eric Badger, Peter Zijlstra, Catalin Marinas, Dave Hansen,
Jason Gunthorpe, Logan Gunthorpe, Ingo Molnar, Borislav Petkov,
Andy Lutomirski, Thomas Gleixner, Will Deacon, Christoph Hellwig
In-Reply-To: <20200306170846.9333-1-logang@deltatee.com>
PCI BAR IO memory should never be mapped as WB, however prior to this
the PAT bits were set WB and it was typically overridden by MTRR
registers set by the firmware.
Set PCI P2PDMA memory to be UC as this is what it currently, typically,
ends up being mapped as on x86 after the MTRR registers override the
cache setting.
Future use-cases may need to generalize this by adding flags to
select the caching type, as some P2PDMA cases may not want UC.
However, those use-cases are not upstream yet and this can be changed
when they arrive.
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
---
mm/memremap.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/mm/memremap.c b/mm/memremap.c
index 06742372a203..9033ae401448 100644
--- a/mm/memremap.c
+++ b/mm/memremap.c
@@ -190,7 +190,10 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid)
}
break;
case MEMORY_DEVICE_DEVDAX:
+ need_devmap_managed = false;
+ break;
case MEMORY_DEVICE_PCI_P2PDMA:
+ params.pgprot = pgprot_noncached(params.pgprot);
need_devmap_managed = false;
break;
default:
--
2.20.1
^ permalink raw reply related
* Re: [PATCH v2 4/5] powerpc/sysfs: Show idle_purr and idle_spurr for every CPU
From: Naveen N. Rao @ 2020-03-06 17:35 UTC (permalink / raw)
To: Nathan Lynch
Cc: ego, Tyrel Datwyler, linux-kernel, Kamalesh Babulal,
Vaidyanathan Srinivasan, linuxppc-dev
In-Reply-To: <87wo7xju0k.fsf@linux.ibm.com>
Nathan Lynch wrote:
> "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> writes:
>> Gautham R Shenoy wrote:
>>> On Fri, Feb 21, 2020 at 10:50:12AM -0600, Nathan Lynch wrote:
>>>> It's regrettable that we have to wake up potentially idle CPUs in order
>>>> to derive correct idle statistics for them, but I suppose the main user
>>>> (lparstat) of these interfaces already is causing this to happen by
>>>> polling the existing per-cpu purr and spurr attributes.
>>>>
>>>> So now lparstat will incur at minimum four syscalls and four IPIs per
>>>> CPU per polling interval -- one for each of purr, spurr, idle_purr and
>>>> idle_spurr. Correct?
>>>
>>> Yes, it is unforunate that we will end up making four syscalls and
>>> generating IPI noise, and this is something that I discussed with
>>> Naveen and Kamalesh. We have the following two constraints:
>>>
>>> 1) These values of PURR and SPURR required are per-cpu. Hence putting
>>> them in lparcfg is not an option.
>>>
>>> 2) sysfs semantics encourages a single value per key, the key being
>>> the sysfs-file. Something like the following would have made far more
>>> sense.
>>>
>>> cat /sys/devices/system/cpu/cpuX/purr_spurr_accounting
>>> purr:A
>>> idle_purr:B
>>> spurr:C
>>> idle_spurr:D
>>>
>>> There are some sysfs files which allow something like this. Eg:
>>> /sys/devices/system/cpu/cpu0/cpufreq/stats/time_in_state
>>>
>>> Thoughts on any other alternatives?
>>
>> Umm... procfs?
>> /me ducks
>
> I had wondered about perf events but I'm not sure that's any more suitable.
Yes, we considered that, but it looks like the event reads are not
"batched" in any manner. So, the IPI overhead will be similar.
>
>>>> At some point it's going to make sense to batch sampling of remote CPUs'
>>>> SPRs.
>>
>> How did you mean this? It looks like we first need to provide a separate
>> user interface, since with the existing sysfs interface providing
>> separate files, I am not sure if we can batch such reads.
>
> I mean in order to minimize IPI traffic something like: sample/calculate
> all of a CPU's purr, idle_purr, spurr, idle_spurr in a single IPI upon a
> read of any of the attributes, and cache the result for some time, so
> that the anticipated subsequent reads of the other attributes use the
> cached results instead of generating more IPIs.
>
> That would keep the current sysfs interface at the cost of imposing a
> certain coarseness in the results.
Thanks for clarifying, that makes sense. Though we need to be careful in
ensuring the sysfs semantics work as expected.
>
> Anyway, that's a mitigation that could be considered if the
> implementation in this patch is found to be too expensive in practice.
That's a good point. We can optimize later if this turns out to be a
problem in practice, if we end up using this approach.
- Naveen
^ permalink raw reply
* [PATCH v3] ima: add a new CONFIG for loading arch-specific policies
From: Nayna Jain @ 2020-03-06 17:39 UTC (permalink / raw)
To: linux-integrity, linuxppc-dev, linux-efi, linux-s390
Cc: Nayna Jain, linux-kernel, zohar, Philipp Rudo, Ard Biesheuvel
Every time a new architecture defines the IMA architecture specific
functions - arch_ima_get_secureboot() and arch_ima_get_policy(), the IMA
include file needs to be updated. To avoid this "noise", this patch
defines a new IMA Kconfig IMA_SECURE_AND_OR_TRUSTED_BOOT option, allowing
the different architectures to select it.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Philipp Rudo <prudo@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
---
v3:
* Updated and tested the patch with improvements suggested by Michael.
It now uses "imply" instead of "select". Thanks Michael.
* Have missed replacing the CONFIG_IMA in x86 and s390 with new config,
that was resulting in redefinition when the IMA_SECURE_AND_OR_TRUSTED_BOOT
is not enabled. Thanks to Mimi for recognizing the problem.
v2:
* Fixed the issue identified by Mimi. Thanks Mimi, Ard, Heiko and Michael for
discussing the fix.
arch/powerpc/Kconfig | 1 +
arch/s390/Kconfig | 1 +
arch/s390/kernel/Makefile | 2 +-
arch/x86/Kconfig | 1 +
arch/x86/kernel/Makefile | 2 +-
include/linux/ima.h | 3 +--
security/integrity/ima/Kconfig | 8 ++++++++
7 files changed, 14 insertions(+), 4 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 497b7d0b2d7e..a5cfde432983 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -979,6 +979,7 @@ config PPC_SECURE_BOOT
bool
depends on PPC_POWERNV
depends on IMA_ARCH_POLICY
+ select IMA_SECURE_AND_OR_TRUSTED_BOOT
help
Systems with firmware secure boot enabled need to define security
policies to extend secure boot to the OS. This config allows a user
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 8abe77536d9d..4a502fbcb800 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -195,6 +195,7 @@ config S390
select ARCH_HAS_FORCE_DMA_UNENCRYPTED
select SWIOTLB
select GENERIC_ALLOCATOR
+ select IMA_SECURE_AND_OR_TRUSTED_BOOT if IMA_ARCH_POLICY
config SCHED_OMIT_FRAME_POINTER
diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile
index 2b1203cf7be6..578a6fa82ea4 100644
--- a/arch/s390/kernel/Makefile
+++ b/arch/s390/kernel/Makefile
@@ -70,7 +70,7 @@ obj-$(CONFIG_JUMP_LABEL) += jump_label.o
obj-$(CONFIG_KEXEC_FILE) += machine_kexec_file.o kexec_image.o
obj-$(CONFIG_KEXEC_FILE) += kexec_elf.o
-obj-$(CONFIG_IMA) += ima_arch.o
+obj-$(CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT) += ima_arch.o
obj-$(CONFIG_PERF_EVENTS) += perf_event.o perf_cpum_cf_common.o
obj-$(CONFIG_PERF_EVENTS) += perf_cpum_cf.o perf_cpum_sf.o
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index beea77046f9b..7f5bfaf0cbd2 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -230,6 +230,7 @@ config X86
select VIRT_TO_BUS
select X86_FEATURE_NAMES if PROC_FS
select PROC_PID_ARCH_STATUS if PROC_FS
+ select IMA_SECURE_AND_OR_TRUSTED_BOOT if EFI && IMA_ARCH_POLICY
config INSTRUCTION_DECODER
def_bool y
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 9b294c13809a..7f131ceba136 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -155,5 +155,5 @@ ifeq ($(CONFIG_X86_64),y)
endif
ifdef CONFIG_EFI
-obj-$(CONFIG_IMA) += ima_arch.o
+obj-$(CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT) += ima_arch.o
endif
diff --git a/include/linux/ima.h b/include/linux/ima.h
index 1659217e9b60..aefe758f4466 100644
--- a/include/linux/ima.h
+++ b/include/linux/ima.h
@@ -30,8 +30,7 @@ extern void ima_kexec_cmdline(const void *buf, int size);
extern void ima_add_kexec_buffer(struct kimage *image);
#endif
-#if (defined(CONFIG_X86) && defined(CONFIG_EFI)) || defined(CONFIG_S390) \
- || defined(CONFIG_PPC_SECURE_BOOT)
+#ifdef CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT
extern bool arch_ima_get_secureboot(void);
extern const char * const *arch_get_ima_policy(void);
#else
diff --git a/security/integrity/ima/Kconfig b/security/integrity/ima/Kconfig
index 3f3ee4e2eb0d..2baaf196c6d8 100644
--- a/security/integrity/ima/Kconfig
+++ b/security/integrity/ima/Kconfig
@@ -327,3 +327,11 @@ config IMA_QUEUE_EARLY_BOOT_KEYS
depends on IMA_MEASURE_ASYMMETRIC_KEYS
depends on SYSTEM_TRUSTED_KEYRING
default y
+
+config IMA_SECURE_AND_OR_TRUSTED_BOOT
+ bool
+ depends on IMA_ARCH_POLICY
+ default n
+ help
+ This option is selected by architectures to enable secure and/or
+ trusted boot based on IMA runtime policies.
--
2.18.1
^ permalink raw reply related
* Re: [PATCH v3] ima: add a new CONFIG for loading arch-specific policies
From: Nayna @ 2020-03-06 17:59 UTC (permalink / raw)
To: Nayna Jain, linux-integrity, linuxppc-dev, linux-efi, linux-s390,
zohar, Philipp Rudo, Ard Biesheuvel
Cc: linux-kernel
In-Reply-To: <1583516360-22016-1-git-send-email-nayna@linux.ibm.com>
Oops, Please ignore this patch.
By mistake I posted the wrong version. I am sorry for the confusion, I
will resend the right version.
Thanks & Regards,
- Nayna
On 3/6/20 12:39 PM, Nayna Jain wrote:
> Every time a new architecture defines the IMA architecture specific
> functions - arch_ima_get_secureboot() and arch_ima_get_policy(), the IMA
> include file needs to be updated. To avoid this "noise", this patch
> defines a new IMA Kconfig IMA_SECURE_AND_OR_TRUSTED_BOOT option, allowing
> the different architectures to select it.
>
> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
> Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
> Cc: Ard Biesheuvel <ardb@kernel.org>
> Cc: Philipp Rudo <prudo@linux.ibm.com>
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> ---
> v3:
> * Updated and tested the patch with improvements suggested by Michael.
> It now uses "imply" instead of "select". Thanks Michael.
> * Have missed replacing the CONFIG_IMA in x86 and s390 with new config,
> that was resulting in redefinition when the IMA_SECURE_AND_OR_TRUSTED_BOOT
> is not enabled. Thanks to Mimi for recognizing the problem.
>
> v2:
> * Fixed the issue identified by Mimi. Thanks Mimi, Ard, Heiko and Michael for
> discussing the fix.
>
> arch/powerpc/Kconfig | 1 +
> arch/s390/Kconfig | 1 +
> arch/s390/kernel/Makefile | 2 +-
> arch/x86/Kconfig | 1 +
> arch/x86/kernel/Makefile | 2 +-
> include/linux/ima.h | 3 +--
> security/integrity/ima/Kconfig | 8 ++++++++
> 7 files changed, 14 insertions(+), 4 deletions(-)
>
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index 497b7d0b2d7e..a5cfde432983 100644
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -979,6 +979,7 @@ config PPC_SECURE_BOOT
> bool
> depends on PPC_POWERNV
> depends on IMA_ARCH_POLICY
> + select IMA_SECURE_AND_OR_TRUSTED_BOOT
> help
> Systems with firmware secure boot enabled need to define security
> policies to extend secure boot to the OS. This config allows a user
> diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
> index 8abe77536d9d..4a502fbcb800 100644
> --- a/arch/s390/Kconfig
> +++ b/arch/s390/Kconfig
> @@ -195,6 +195,7 @@ config S390
> select ARCH_HAS_FORCE_DMA_UNENCRYPTED
> select SWIOTLB
> select GENERIC_ALLOCATOR
> + select IMA_SECURE_AND_OR_TRUSTED_BOOT if IMA_ARCH_POLICY
>
>
> config SCHED_OMIT_FRAME_POINTER
> diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile
> index 2b1203cf7be6..578a6fa82ea4 100644
> --- a/arch/s390/kernel/Makefile
> +++ b/arch/s390/kernel/Makefile
> @@ -70,7 +70,7 @@ obj-$(CONFIG_JUMP_LABEL) += jump_label.o
> obj-$(CONFIG_KEXEC_FILE) += machine_kexec_file.o kexec_image.o
> obj-$(CONFIG_KEXEC_FILE) += kexec_elf.o
>
> -obj-$(CONFIG_IMA) += ima_arch.o
> +obj-$(CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT) += ima_arch.o
>
> obj-$(CONFIG_PERF_EVENTS) += perf_event.o perf_cpum_cf_common.o
> obj-$(CONFIG_PERF_EVENTS) += perf_cpum_cf.o perf_cpum_sf.o
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index beea77046f9b..7f5bfaf0cbd2 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -230,6 +230,7 @@ config X86
> select VIRT_TO_BUS
> select X86_FEATURE_NAMES if PROC_FS
> select PROC_PID_ARCH_STATUS if PROC_FS
> + select IMA_SECURE_AND_OR_TRUSTED_BOOT if EFI && IMA_ARCH_POLICY
>
> config INSTRUCTION_DECODER
> def_bool y
> diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
> index 9b294c13809a..7f131ceba136 100644
> --- a/arch/x86/kernel/Makefile
> +++ b/arch/x86/kernel/Makefile
> @@ -155,5 +155,5 @@ ifeq ($(CONFIG_X86_64),y)
> endif
>
> ifdef CONFIG_EFI
> -obj-$(CONFIG_IMA) += ima_arch.o
> +obj-$(CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT) += ima_arch.o
> endif
> diff --git a/include/linux/ima.h b/include/linux/ima.h
> index 1659217e9b60..aefe758f4466 100644
> --- a/include/linux/ima.h
> +++ b/include/linux/ima.h
> @@ -30,8 +30,7 @@ extern void ima_kexec_cmdline(const void *buf, int size);
> extern void ima_add_kexec_buffer(struct kimage *image);
> #endif
>
> -#if (defined(CONFIG_X86) && defined(CONFIG_EFI)) || defined(CONFIG_S390) \
> - || defined(CONFIG_PPC_SECURE_BOOT)
> +#ifdef CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT
> extern bool arch_ima_get_secureboot(void);
> extern const char * const *arch_get_ima_policy(void);
> #else
> diff --git a/security/integrity/ima/Kconfig b/security/integrity/ima/Kconfig
> index 3f3ee4e2eb0d..2baaf196c6d8 100644
> --- a/security/integrity/ima/Kconfig
> +++ b/security/integrity/ima/Kconfig
> @@ -327,3 +327,11 @@ config IMA_QUEUE_EARLY_BOOT_KEYS
> depends on IMA_MEASURE_ASYMMETRIC_KEYS
> depends on SYSTEM_TRUSTED_KEYRING
> default y
> +
> +config IMA_SECURE_AND_OR_TRUSTED_BOOT
> + bool
> + depends on IMA_ARCH_POLICY
> + default n
> + help
> + This option is selected by architectures to enable secure and/or
> + trusted boot based on IMA runtime policies.
^ permalink raw reply
* Re: [PATCH] selftests/powerpc: Add a test of sigreturn vs VDSO
From: Nathan Lynch @ 2020-03-06 18:25 UTC (permalink / raw)
To: Michael Ellerman; +Cc: linuxppc-dev
In-Reply-To: <20200304110402.6038-1-mpe@ellerman.id.au>
Michael Ellerman <mpe@ellerman.id.au> writes:
> +static int search_proc_maps(char *needle, unsigned long *low, unsigned long *high)
^^ const?
> +{
> + unsigned long start, end;
> + static char buf[4096];
> + char name[128];
> + FILE *f;
> + int rc = -1;
> +
> + f = fopen("/proc/self/maps", "r");
> + if (!f) {
> + perror("fopen");
> + return -1;
> + }
> +
> + while (fgets(buf, sizeof(buf), f)) {
> + rc = sscanf(buf, "%lx-%lx %*c%*c%*c%*c %*x %*d:%*d %*d %127s\n",
> + &start, &end, name);
I suspect it doesn't matter in practice for this particular test, but
since this looks like a generally useful function that could gain users
in the future: does this spuriously fail if the matching line straddles
a 4096-byte boundary? Maybe fscanf(3) should be used instead?
> + if (rc == 2)
> + continue;
> +
> + if (rc != 3) {
> + printf("sscanf errored\n");
> + rc = -1;
> + break;
> + }
> +
> + if (strstr(name, needle)) {
> + *low = start;
> + *high = end - 1;
> + rc = 0;
> + break;
> + }
> + }
> +
> + fclose(f);
> +
> + return rc;
> +}
> +
> +static volatile sig_atomic_t took_signal = 0;
> +
> +static void sigusr1_handler(int sig)
> +{
> + took_signal++;
> +}
> +
> +int test_sigreturn_vdso(void)
> +{
> + unsigned long low, high, size;
> + struct sigaction act;
> + char *p;
> +
> + act.sa_handler = sigusr1_handler;
> + act.sa_flags = 0;
> + sigemptyset(&act.sa_mask);
> +
> + assert(sigaction(SIGUSR1, &act, NULL) == 0);
> +
> + // Confirm the VDSO is mapped, and work out where it is
> + assert(search_proc_maps("[vdso]", &low, &high) == 0);
> + size = high - low + 1;
> + printf("VDSO is at 0x%lx-0x%lx (%lu bytes)\n", low, high, size);
> +
> + kill(getpid(), SIGUSR1);
> + assert(took_signal == 1);
> + printf("Signal delivered OK with VDSO mapped\n");
I haven't looked at the test harness in detail but this should be
reliable if the program is a single thread - lgtm.
^ permalink raw reply
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