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Before this patch csky-linux need CONFIG_RAM_BASE to determine start
physical address. Now we use phys_offset variable to replace the macro
of PHYS_OFFSET and we setup phys_offset with real physical address which
is determined during startup in head.S.
With this patch we needn't re-compile kernel for different start
physical address. ie: 0x0 / 0xc0000000 start physical address could use
the same vmlinux, be care different start address must be 512MB aligned.
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>
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Linux kernel has provided some apis for arch signal's implementation.
For example:
restore_saved_sigmask()
set_current_blocked()
restore_altstack()
But in last version of csky signal.c didn't use them and some codes are
confusing, so reconstruct signal.c with reference to riscv's code.
Now csky signal.c implementation are very close to riscv and we can
get the following benefits:
- Clear code structure
- The signal code of riscv and csky can be reviewed together
- Promoting the unification of arch's signal implementation
Also modified the related code in entry.S
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>
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We could use regs->sr 16-24 bits to detect syscall: VEC_TRAP0 and
r11_sig is no necessary for current implementation.
In this patch, we implement the in_syscall and forget_syscall which are
inspired from arm & nds32, but csky pt_regs has no syscall_num element
and we just set zero to regs->sr's vector-bits-field instead.
For ret_from_fork, current task was forked from parent which is in syscall
progress and its regs->sr has been already setted with VEC_TRAP0. See:
arch/csky/kernel/process.c: copy_thread()
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
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Move #ifdef __KERNEL__ code in the uapi namespace to non-uapi
include/asm/ptrace.h namespace and remove #ifdef __KERNEL__ in
include/asm/ptrace.h. Seperate ptrace.h in uapi and non-uapi is more
common and clear.
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Dmitry V. Levin <ldv@altlinux.org>
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Remove duplicate header which is included twice.
Signed-off-by: Jagadeesh Pagadala <jagdsh.linux@gmail.com>
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
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Since commit 7cbbbb8bc297 ("kbuild: warn redundant generic-y"),
redundant generic-y is reported. I missed to delete this one.
scripts/Makefile.asm-generic:25: redundant generic-y found in arch/csky/include/asm/Kbuild: ftrace.h
In this case, csky-specific implementation exists in
arch/csky/include/asm/ftrace.h
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
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Previous syscall_trace implementation couldn't support AUDITSYSCALL and
SYSCALL_TRACEPOINTS. Now we redesign it to support audit_syscall
and syscall_tracepoints just like other archs'.
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Dmitry V. Levin <ldv@altlinux.org>
Cc: Arnd Bergmann <arnd@arndb.de>
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This patch add support for perf callchain sampling on csky platform.
As fp is used to unwind the stack, the program being sampled and the
C library need to be compiled with -mbacktrace for user callchains,
kernel callchains require CONFIG_STACKTRACE = y.
Changelog:
- Coding convention with Christoph's advice for riscv's.
Signed-off-by: Mao Han <han_mao@c-sky.com>
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Christoph Hellwig <hch@infradead.org>
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Support dynamic ftrace including dynamic graph tracer. Gcc-csky with -pg
will produce call site in every function prologue and we can use these
call site to hook trace function.
gcc with -pg origin call site:
push lr
jbsr _mcount
nop32
nop32
If the (callee - caller)'s offset is in range of bsr instruction, we'll
modify code with:
push lr
bsr _mcount
nop32
nop32
Else if the (callee - caller)'s offset is out of bsr instrunction, we'll
modify code with:
push lr
movih r26, ...
ori r26, ...
jsr r26
(r26 is reserved for jsr link reg in csky abiv2 spec.)
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
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This fixup is continue to commit 35ff802af1c4 (csky: fixup remove
vdsp implement for kernel.) and in that patch I didn't finish the
job. We must forbid gcc to generate any vdsp & fpu instructions
and remove vdsp asm in memmove.S.
eg: For GCC it's -mcpu=ck860 and For AS it's -Wa,-mcpu=ck860fv
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
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lx2160a supports pw20 which could help save more power during cpu is
dile. It needs system firmware support via PSCI.
Signed-off-by: Ran Wang <ran.wang_1@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
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v2 of "clk: imx: Refactor entire sccg pll clk" dropped the implicit
reparenting of the PLL output from the bypass clock to the real
PLL. The commit introducing the GPU node had only been tested against
v1 of this patch. Without an explicit reparent to the real PLL the
GPU is stuck at the bypass clock rate of 25MHz, serverly hampering
performance.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Abel Vesa <abel.vesa@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
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Link the SW1AB regulator to the GPU domain, so that it gets enabled
when needed.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
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This is very similar to imx8mq cpufreq-dt support.
Operating points are from datasheet:
https://www.nxp.com/docs/en/data-sheet/IMX8MMCEC.pdf
Higher opps were omitted (just like imx8mq) because it requires checking
speed grade from OCOTP fuses.
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
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Add an initial description of the i2c1 bus with a pca9646 i2c switch and
various gpio expanders and sensors behind that. Only add the sensors
which already have upstream drivers.
According to the datasheet the pca9646 is software compatible with
pca9546 so no driver changes should be required.
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
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On i.MX8QXP, SCU uses MU1 general interrupt channel #3 to notify
user for IRQs of RTC alarm, thermal alarm and WDOG etc., mailbox
RX doorbell mode is used for this function, this patch adds
support for it.
Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Reviewed-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
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This enables the Vivante GC7000L GPU on the i.MX8MQ SoC.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Guido Günther <agx@sigxcpu.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
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The Zii Ultra design, also known as RDU3, is the i.MX8M based successor
to the the i.MX6 based RDU2. This adds the basic board support for all
components which are supported by the upstream kernel at this time.
The board comes in 2 different versions, called RMB3 and Zest, which
are derived from the same design, but have different layouts and a
few small differences in the populated components.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
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Specify CS as GPIO_ACTIVE_LOW in spi0 to fix the following warning:
m25p128@0 enforce active low on chipselect handle
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
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Mark i2c0 SCL as GPIO_OPEN_DRAIN to fix the following warning:
gpio-36 (scl): enforced open drain please flag it properly in DT/ACPI DSDT/board file
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
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Add support for ZII's i.MX7 based Remote Peripheral Unit 2 (RPU2)
board.
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Rob Herring <robh@kernel.org>
Cc: linux-kernel@vger.kernel.org
Cc: devicetree@vger.kernel.org
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
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Running reboot command on the TQMa7 board would just hang infinite
at the end of the system shutdown process.
Handling of i.MX7 errata e10574:
Watchdog: A watchdog timeout or software trigger will not reset the SOC.
Moved pinctrl from common mba7 to common tqma7 dtsi as it improves
readability of errata handling. Most integrators of this SoM will
likely use the development board as inspiration for handling this
SoC issue.
Signed-off-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
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So we are going to be staring at those in the next years, let's make
them more succinct. In particular:
- change "address = " to "address: "
- "-privileged" reads funny. It should be simply "kernel" or "user"
- "from kernel code" reads funny too. "kernel mode" or "user mode" is
more natural.
An actual example says more than 1000 words, of course:
[ 0.248370] BUG: kernel NULL pointer dereference, address: 00000000000005b8
[ 0.249120] #PF: supervisor write access in kernel mode
[ 0.249717] #PF: error_code(0x0002) - not-present page
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dave.hansen@linux.intel.com
Cc: luto@kernel.org
Cc: riel@surriel.com
Cc: sean.j.christopherson@intel.com
Cc: yu-cheng.yu@intel.com
Link: http://lkml.kernel.org/r/20190421183524.GC6048@zn.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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There is currently no DT binding for GPIO rfkill signals. To make
mini-PCIe attached WiFi devices work, use gpio-hog to hold the
wlan_disable signal de-asserted.
Signed-off-by: Thomas Schreiber <tschreibe@gmail.com>
[baruch: add pinctrl node; rename tag]
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
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Kirkwood has always had the ability to retrieve the local-mac-address
from the hardware (usually this was configured by the bootloader). This
is particularly useful when dealing with a legacy non-DT aware
bootloader.
The "error" message just indicated that the board used an old bootloader
and in many cases users can't do anything about this. The message
probably should have been pr_info() to inform the user that the kernel
has been helpful but rather than than let's remove it entirely to make
the kernel less noisy.
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
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The first interrupt is for the regular watchdog timeout. Normally the
RSTOUT line will trigger a reset before this interrupt fires but on
systems with a non-standard reset it may still trigger.
The second interrupt is for a timer1 which is used as a pre-timeout for
the watchdog.
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
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The mv-xor DMA driver is used for the XOR engine found in the ARM64
Marvell Armada 3720 SoC, so it makes sense to have it enabled in the
arm64 defconfig. A recent boot-time regression was found in mv-xor,
which would have been more easily noticed with this driver enabled by
default.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
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This patch fix the below section mismatch warnings.
WARNING: vmlinux.o(.text+0x2d1f44): Section mismatch in reference from the function devm_memremap_pages_release() to the function .meminit.text:arch_remove_memory()
WARNING: vmlinux.o(.text+0x2d265c): Section mismatch in reference from the function devm_memremap_pages() to the function .meminit.text:arch_add_memory()
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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The region actually point to linear map. Rename the #define to
clarify thati.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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This helps in debugging. We can look at the dmesg to find out
different kernel mapping details.
On 4K config this shows
kernel vmalloc start = 0xc000100000000000
kernel IO start = 0xc000200000000000
kernel vmemmap start = 0xc000300000000000
On 64K config:
kernel vmalloc start = 0xc008000000000000
kernel IO start = 0xc00a000000000000
kernel vmemmap start = 0xc00c000000000000
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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This reduces multiple comparisons in get_region_id to a bit shift operation.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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All the regions are now mapped with top nibble 0xc. Hence the region id
check is not needed for virt_addr_valid()
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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This adds an explicit check in various functions.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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This patch maps vmalloc, IO and vmemap regions in the 0xc address range
instead of the current 0xd and 0xf range. This brings the mapping closer
to radix translation mode.
With hash 64K page size each of this region is 512TB whereas with 4K config
we are limited by the max page table range of 64TB and hence there regions
are of 16TB size.
The kernel mapping is now:
On 4K hash
kernel_region_map_size = 16TB
kernel vmalloc start = 0xc000100000000000
kernel IO start = 0xc000200000000000
kernel vmemmap start = 0xc000300000000000
64K hash, 64K radix and 4k radix:
kernel_region_map_size = 512TB
kernel vmalloc start = 0xc008000000000000
kernel IO start = 0xc00a000000000000
kernel vmemmap start = 0xc00c000000000000
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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This makes it easy to update the region mapping in the later patch
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Allocate subpage protect related variables only if we use the feature.
This helps in reducing the hash related mm context struct by around 4K
Before the patch
sizeof(struct hash_mm_context) = 8288
After the patch
sizeof(struct hash_mm_context) = 4160
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Currently, our mm_context_t on book3s64 include all hash specific
context details like slice mask and subpage protection details. We
can skip allocating these with radix translation. This will help us to save
8K per mm_context with radix translation.
With the patch applied we have
sizeof(mm_context_t) = 136
sizeof(struct hash_mm_context) = 8288
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Avoid #ifdef in generic code. Also enables us to do this specific to
MMU translation mode on book3s64
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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We want to switch to allocating them runtime only when hash translation is
enabled. Add helpers so that both book3s and nohash can be adapted to
upcoming change easily.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Book3s64 always have PPC_MM_SLICES enabled. So remove the unncessary #ifdef
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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The current value of MAX_PHYSMEM_BITS cannot work with 32 bit configs.
We used to have MAX_PHYSMEM_BITS not defined without SPARSEMEM and 32
bit configs never expected a value to be set for MAX_PHYSMEM_BITS.
Dependent code such as zsmalloc derived the right values based on other
fields. Instead of finding a value that works with different configs,
use new values only for book3s_64. For 64 bit booke, use the definition
of MAX_PHYSMEM_BITS as per commit a7df61a0e2b6 ("[PATCH] ppc64: Increase sparsemem defaults")
That change was done in 2005 and hopefully will work with book3e 64.
Fixes: 8bc086899816 ("powerpc/mm: Only define MAX_PHYSMEM_BITS in SPARSEMEM configurations")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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This patch implements Kernel Userspace Access Protection for
book3s/32.
Due to limitations of the processor page protection capabilities,
the protection is only against writing. read protection cannot be
achieved using page protection.
The previous patch modifies the page protection so that RW user
pages are RW for Key 0 and RO for Key 1, and it sets Key 0 for
both user and kernel.
This patch changes userspace segment registers are set to Ku 0
and Ks 1. When kernel needs to write to RW pages, the associated
segment register is then changed to Ks 0 in order to allow write
access to the kernel.
In order to avoid having the read all segment registers when
locking/unlocking the access, some data is kept in the thread_struct
and saved on stack on exceptions. The field identifies both the
first unlocked segment and the first segment following the last
unlocked one. When no segment is unlocked, it contains value 0.
As the hash_page() function is not able to easily determine if a
protfault is due to a bad kernel access to userspace, protfaults
need to be handled by handle_page_fault when KUAP is set.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Drop allow_read/write_to/from_user() as they're now in kup.h,
and adapt allow_user_access() to do nothing when to == NULL]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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This patch prepares Kernel Userspace Access Protection for
book3s/32.
Due to limitations of the processor page protection capabilities,
the protection is only against writing. read protection cannot be
achieved using page protection.
book3s/32 provides the following values for PP bits:
PP00 provides RW for Key 0 and NA for Key 1
PP01 provides RW for Key 0 and RO for Key 1
PP10 provides RW for all
PP11 provides RO for all
Today PP10 is used for RW pages and PP11 for RO pages, and user
segment register's Kp and Ks are set to 1. This patch modifies
page protection to use PP01 for RW pages and sets user segment
registers to Kp 0 and Ks 0.
This will allow to setup Userspace write access protection by
settng Ks to 1 in the following patch.
Kernel space segment registers remain unchanged.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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To implement Kernel Userspace Execution Prevention, this patch
sets NX bit on all user segments on kernel entry and clears NX bit
on all user segments on kernel exit.
Note that powerpc 601 doesn't have the NX bit, so KUEP will not
work on it. A warning is displayed at startup.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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This patch adds Kernel Userspace Access Protection on the 8xx.
When a page is RO or RW, it is set RO or RW for Key 0 and NA
for Key 1.
Up to now, the User group is defined with Key 0 for both User and
Supervisor.
By changing the group to Key 0 for User and Key 1 for Supervisor,
this patch prevents the Kernel from being able to access user data.
At exception entry, the kernel saves SPRN_MD_AP in the regs struct,
and reapply the protection. At exception exit it restores SPRN_MD_AP
with the value saved on exception entry.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Drop allow_read/write_to/from_user() as they're now in kup.h]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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This patch adds Kernel Userspace Execution Prevention on the 8xx.
When a page is Executable, it is set Executable for Key 0 and NX
for Key 1.
Up to now, the User group is defined with Key 0 for both User and
Supervisor.
By changing the group to Key 0 for User and Key 1 for Supervisor,
this patch prevents the Kernel from being able to execute user code.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Since the 8xx implements hardware page table walk assistance,
the PGD entries always point to a 4k aligned page, so the 2 upper
bits of the APG are not clobbered anymore and remain 0. Therefore
only APG0 and APG1 are used and need a definition. We set the
other APG to the lowest permission level.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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This patch adds ASM macros for saving, restoring and checking
the KUAP state, and modifies setup_32 to call them on exceptions
from kernel.
The macros are defined as empty by default for when CONFIG_PPC_KUAP
is not selected and/or for platforms which don't handle (yet) KUAP.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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syscalls are from user only, so we can account time without checking
whether returning to kernel or user as it will only be user.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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When KUAP is enabled we have logic to detect page faults that occur
outside of a valid user access region and are blocked by the AMR.
What we don't have at the moment is logic to detect a fault *within* a
valid user access region, that has been incorrectly blocked by AMR.
This is not meant to ever happen, but it can if we incorrectly
save/restore the AMR, or if the AMR was overwritten for some other
reason.
Currently if that happens we assume it's just a regular fault that
will be corrected by handling the fault normally, so we just return.
But there is nothing the fault handling code can do to fix it, so the
fault just happens again and we spin forever, leading to soft lockups.
So add some logic to detect that case and WARN() if we ever see it.
Arguably it should be a BUG(), but it's more polite to fail the access
and let the kernel continue, rather than taking down the box. There
should be no data integrity issue with failing the fault rather than
BUG'ing, as we're just going to disallow an access that should have
been allowed.
To make the code a little easier to follow, unroll the condition at
the end of bad_kernel_fault() and comment each case, before adding the
call to bad_kuap_fault().
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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