[ Upstream commit d11a69873d ]
Arm platforms use is_default_overflow_handler() to determine if the
hw_breakpoint code should single-step over the breakpoint trigger or
let the custom handler deal with it.
Since bpf_overflow_handler() currently isn't recognized as a default
handler, attaching a BPF program to a PERF_TYPE_BREAKPOINT event causes
it to keep firing (the instruction triggering the data abort exception
is never skipped). For example:
# bpftrace -e 'watchpoint:0x10000:4:w { print("hit") }' -c ./test
Attaching 1 probe...
hit
hit
[...]
^C
(./test performs a single 4-byte store to 0x10000)
This patch replaces the check with uses_default_overflow_handler(),
which accounts for the bpf_overflow_handler() case by also testing
if one of the perf_event_output functions gets invoked indirectly,
via orig_default_handler.
Signed-off-by: Tomislav Novak <tnovak@meta.com>
Tested-by: Samuel Gosselin <sgosselin@google.com> # arm64
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/linux-arm-kernel/20220923203644.2731604-1-tnovak@fb.com/
Link: https://lore.kernel.org/r/20230605191923.1219974-1-tnovak@meta.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit fa3eeb638d ]
When unwind instruction is 0xb2,the subsequent instructions
are uleb128 bytes.
For now,it uses only the first uleb128 byte in code.
For vsp increments of 0x204~0x400,use one uleb128 byte like below:
0xc06a00e4 <unwind_test_work>: 0x80b27fac
Compact model index: 0
0xb2 0x7f vsp = vsp + 1024
0xac pop {r4, r5, r6, r7, r8, r14}
For vsp increments larger than 0x400,use two uleb128 bytes like below:
0xc06a00e4 <unwind_test_work>: @0xc0cc9e0c
Compact model index: 1
0xb2 0x81 0x01 vsp = vsp + 1032
0xac pop {r4, r5, r6, r7, r8, r14}
The unwind works well since the decoded uleb128 byte is also 0x81.
For vsp increments larger than 0x600,use two uleb128 bytes like below:
0xc06a00e4 <unwind_test_work>: @0xc0cc9e0c
Compact model index: 1
0xb2 0x81 0x02 vsp = vsp + 1544
0xac pop {r4, r5, r6, r7, r8, r14}
In this case,the decoded uleb128 result is 0x101(vsp=0x204+(0x101<<2)).
While the uleb128 used in code is 0x81(vsp=0x204+(0x81<<2)).
The unwind aborts at this frame since it gets incorrect vsp.
To fix this,add uleb128 decode to cover all the above case.
Signed-off-by: Haibo Li <haibo.li@mediatek.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 0e25498f8c upstream.
There are two big uses of do_exit. The first is it's design use to be
the guts of the exit(2) system call. The second use is to terminate
a task after something catastrophic has happened like a NULL pointer
in kernel code.
Add a function make_task_dead that is initialy exactly the same as
do_exit to cover the cases where do_exit is called to handle
catastrophic failure. In time this can probably be reduced to just a
light wrapper around do_task_dead. For now keep it exactly the same so
that there will be no behavioral differences introducing this new
concept.
Replace all of the uses of do_exit that use it for catastraphic
task cleanup with make_task_dead to make it clear what the code
is doing.
As part of this rename rewind_stack_do_exit
rewind_stack_and_make_dead.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 3c9f5708b7 upstream
This patch replaces 6 IWMMXT instructions Clang's integrated assembler
does not support in iwmmxt.S using macros, while making sure GNU
assembler still emit the same instructions. This should be easier than
providing full IWMMXT support in Clang. This is one of the last bits of
kernel code that could be compiled but not assembled with clang. Once
all of it works with IAS, we no longer need to special-case 32-bit Arm
in Kbuild, or turn off CONFIG_IWMMXT when build-testing.
"Intel Wireless MMX Technology - Developer Guide - August, 2002" should
be referenced for the encoding schemes of these extensions.
Link: https://github.com/ClangBuiltLinux/linux/issues/975
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Suggested-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Jian Cai <jiancai@google.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3cfb301997 ]
In Thumb2, 'b . + 4' produces a branch instruction that uses a narrow
encoding, and so it does not jump to the following instruction as
expected. So use W(b) instead.
Fixes: 6c7cb60bff ("ARM: fix Thumb2 regression with Spectre BHB")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9be4c88bb7 ]
The following KASAN warning is detected by QEMU.
==================================================================
BUG: KASAN: stack-out-of-bounds in unwind_frame+0x508/0x870
Read of size 4 at addr c36bba90 by task cat/163
CPU: 1 PID: 163 Comm: cat Not tainted 5.10.0-rc1 #40
Hardware name: ARM-Versatile Express
[<c0113fac>] (unwind_backtrace) from [<c010e71c>] (show_stack+0x10/0x14)
[<c010e71c>] (show_stack) from [<c0b805b4>] (dump_stack+0x98/0xb0)
[<c0b805b4>] (dump_stack) from [<c0b7d658>] (print_address_description.constprop.0+0x58/0x4bc)
[<c0b7d658>] (print_address_description.constprop.0) from [<c031435c>] (kasan_report+0x154/0x170)
[<c031435c>] (kasan_report) from [<c0113c44>] (unwind_frame+0x508/0x870)
[<c0113c44>] (unwind_frame) from [<c010e298>] (__save_stack_trace+0x110/0x134)
[<c010e298>] (__save_stack_trace) from [<c01ce0d8>] (stack_trace_save+0x8c/0xb4)
[<c01ce0d8>] (stack_trace_save) from [<c0313520>] (kasan_set_track+0x38/0x60)
[<c0313520>] (kasan_set_track) from [<c0314cb8>] (kasan_set_free_info+0x20/0x2c)
[<c0314cb8>] (kasan_set_free_info) from [<c0313474>] (__kasan_slab_free+0xec/0x120)
[<c0313474>] (__kasan_slab_free) from [<c0311e20>] (kmem_cache_free+0x7c/0x334)
[<c0311e20>] (kmem_cache_free) from [<c01c35dc>] (rcu_core+0x390/0xccc)
[<c01c35dc>] (rcu_core) from [<c01013a8>] (__do_softirq+0x180/0x518)
[<c01013a8>] (__do_softirq) from [<c0135214>] (irq_exit+0x9c/0xe0)
[<c0135214>] (irq_exit) from [<c01a40e4>] (__handle_domain_irq+0xb0/0x110)
[<c01a40e4>] (__handle_domain_irq) from [<c0691248>] (gic_handle_irq+0xa0/0xb8)
[<c0691248>] (gic_handle_irq) from [<c0100b0c>] (__irq_svc+0x6c/0x94)
Exception stack(0xc36bb928 to 0xc36bb970)
b920: c36bb9c0 00000000 c0126919 c0101228 c36bb9c0 b76d7730
b940: c36b8000 c36bb9a0 c3335b00 c01ce0d8 00000003 c36bba3c c36bb940 c36bb978
b960: c010e298 c011373c 60000013 ffffffff
[<c0100b0c>] (__irq_svc) from [<c011373c>] (unwind_frame+0x0/0x870)
[<c011373c>] (unwind_frame) from [<00000000>] (0x0)
The buggy address belongs to the page:
page:(ptrval) refcount:0 mapcount:0 mapping:00000000 index:0x0 pfn:0x636bb
flags: 0x0()
raw: 00000000 00000000 ef867764 00000000 00000000 00000000 ffffffff 00000000
page dumped because: kasan: bad access detected
addr c36bba90 is located in stack of task cat/163 at offset 48 in frame:
stack_trace_save+0x0/0xb4
this frame has 1 object:
[32, 48) 'trace'
Memory state around the buggy address:
c36bb980: f1 f1 f1 f1 00 04 f2 f2 00 00 f3 f3 00 00 00 00
c36bba00: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1
>c36bba80: 00 00 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00
^
c36bbb00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
c36bbb80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
There is a same issue on x86 and has been resolved by the commit f7d27c35dd
("x86/mm, kasan: Silence KASAN warnings in get_wchan()").
The solution could be applied to arm architecture too.
Signed-off-by: Lin Yujun <linyujun809@huawei.com>
Reported-by: He Ying <heying24@huawei.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 6c7cb60bff upstream.
When building for Thumb2, the vectors make use of a local label. Sadly,
the Spectre BHB code also uses a local label with the same number which
results in the Thumb2 reference pointing at the wrong place. Fix this
by changing the number used for the Spectre BHB local label.
Fixes: b9baf5c8c5 ("ARM: Spectre-BHB workaround")
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 36168e387f upstream.
ld.lld does not support the NOCROSSREFS directive at the moment, which
breaks the build after commit b9baf5c8c5 ("ARM: Spectre-BHB
workaround"):
ld.lld: error: ./arch/arm/kernel/vmlinux.lds:34: AT expected, but got NOCROSSREFS
Support for this directive will eventually be implemented, at which
point a version check can be added. To avoid breaking the build in the
meantime, just define NOCROSSREFS to nothing when using ld.lld, with a
link to the issue for tracking.
Cc: stable@vger.kernel.org
Fixes: b9baf5c8c5 ("ARM: Spectre-BHB workaround")
Link: https://github.com/ClangBuiltLinux/linux/issues/1609
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 25875aa71d upstream.
The mitigations for Spectre-BHB are only applied when an exception
is taken, but when unprivileged BPF is enabled, userspace can
load BPF programs that can be used to exploit the problem.
When unprivileged BPF is enabled, report the vulnerable status via
the spectre_v2 sysfs file.
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b9baf5c8c5 upstream.
Workaround the Spectre BHB issues for Cortex-A15, Cortex-A57,
Cortex-A72, Cortex-A73 and Cortex-A75. We also include Brahma B15 as
well to be safe, which is affected by Spectre V2 in the same ways as
Cortex-A15.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
[changes due to lack of SYSTEM_FREEING_INITMEM - gregkh]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9dd78194a3 upstream.
As per other architectures, add support for reporting the Spectre
vulnerability status via sysfs CPU.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
[ preserve res variable - gregkh ]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d920eaa4c4 upstream.
The kgdb code needs to register an undef hook for the Thumb UDF
instruction that will fault in order to be functional on Thumb2
platforms.
Reported-by: Johannes Stezenbach <js@sig21.net>
Tested-by: Johannes Stezenbach <js@sig21.net>
Fixes: 5cbad0ebf4 ("kgdb: support for ARCH=arm")
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ff083a2d97 upstream.
Protect perf_guest_cbs with RCU to fix multiple possible errors. Luckily,
all paths that read perf_guest_cbs already require RCU protection, e.g. to
protect the callback chains, so only the direct perf_guest_cbs touchpoints
need to be modified.
Bug #1 is a simple lack of WRITE_ONCE/READ_ONCE behavior to ensure
perf_guest_cbs isn't reloaded between a !NULL check and a dereference.
Fixed via the READ_ONCE() in rcu_dereference().
Bug #2 is that on weakly-ordered architectures, updates to the callbacks
themselves are not guaranteed to be visible before the pointer is made
visible to readers. Fixed by the smp_store_release() in
rcu_assign_pointer() when the new pointer is non-NULL.
Bug #3 is that, because the callbacks are global, it's possible for
readers to run in parallel with an unregisters, and thus a module
implementing the callbacks can be unloaded while readers are in flight,
resulting in a use-after-free. Fixed by a synchronize_rcu() call when
unregistering callbacks.
Bug #1 escaped notice because it's extremely unlikely a compiler will
reload perf_guest_cbs in this sequence. perf_guest_cbs does get reloaded
for future derefs, e.g. for ->is_user_mode(), but the ->is_in_guest()
guard all but guarantees the consumer will win the race, e.g. to nullify
perf_guest_cbs, KVM has to completely exit the guest and teardown down
all VMs before KVM start its module unload / unregister sequence. This
also makes it all but impossible to encounter bug #3.
Bug #2 has not been a problem because all architectures that register
callbacks are strongly ordered and/or have a static set of callbacks.
But with help, unloading kvm_intel can trigger bug #1 e.g. wrapping
perf_guest_cbs with READ_ONCE in perf_misc_flags() while spamming
kvm_intel module load/unload leads to:
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP
CPU: 6 PID: 1825 Comm: stress Not tainted 5.14.0-rc2+ #459
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
RIP: 0010:perf_misc_flags+0x1c/0x70
Call Trace:
perf_prepare_sample+0x53/0x6b0
perf_event_output_forward+0x67/0x160
__perf_event_overflow+0x52/0xf0
handle_pmi_common+0x207/0x300
intel_pmu_handle_irq+0xcf/0x410
perf_event_nmi_handler+0x28/0x50
nmi_handle+0xc7/0x260
default_do_nmi+0x6b/0x170
exc_nmi+0x103/0x130
asm_exc_nmi+0x76/0xbf
Fixes: 39447b386c ("perf: Enhance perf to allow for guest statistic collection from host")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211111020738.2512932-2-seanjc@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8536a5ef88 upstream.
The Thumb2 version of the FP exception handling entry code treats the
register holding the CP number (R8) differently, resulting in the iWMMXT
CP number check to be incorrect.
Fix this by unifying the ARM and Thumb2 code paths, and switch the
order of the additions of the TI_USED_CP offset and the shifted CP
index.
Cc: <stable@vger.kernel.org>
Fixes: b86040a59f ("Thumb-2: Implementation of the unified start-up and exceptions code")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit b3ea5d56f2 ]
Currently the stacktrace on clang compiled arm kernel uses the 'lr'
register to find the first frame address from pt_regs. However, that
is wrong after calling another function, because the 'lr' register
is used by 'bl' instruction and never be recovered.
As same as gcc arm kernel, directly use the frame pointer (r11) of
the pt_regs to find the first frame address.
Note that this fixes kretprobe stacktrace issue only with
CONFIG_UNWINDER_FRAME_POINTER=y. For the CONFIG_UNWINDER_ARM,
we need another fix.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 48ccc8edf5 upstream.
In randconfig builds, we sometimes come across this warning:
arm-linux-gnueabi-ld: XIP start address may cause MPU programming issues
While this is helpful for actual systems to figure out why it
fails, the warning does not provide any benefit for build testing,
so guard it in a check for CONFIG_COMPILE_TEST, which is usually
set on randconfig builds.
Fixes: 216218308c ("ARM: 8713/1: NOMMU: Support MPU in XIP configuration")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fb033c95c9 upstream.
The system currently warns if the config conditions for
building return_address in arch/arm/kernel/return_address.c
are not met, leaving just an EXPORT_SYMBOL_GPL(return_address)
of a function defined to be 'static linline'.
This is a result of aeea3592a1 ("ARM: 8158/1: LLVMLinux: use static inline in ARM ftrace.h").
Since we're not going to build anything other than an exported
symbol for something that is already being defined to be an
inline-able return of NULL, just avoid building the code to
remove the following warning:
Fixes: aeea3592a1 ("ARM: 8158/1: LLVMLinux: use static inline in ARM ftrace.h")
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dad7b9896a upstream.
When building the kernel wtih gcc-10 or higher using the
CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE=y flag, the compiler picks a slightly
different set of registers for the inline assembly in cpu_init() that
subsequently results in a corrupt kernel stack as well as remaining in
FIQ mode. If a banked register is used for the last argument, the wrong
version of that register gets loaded into CPSR_c. When building in Arm
mode, the arguments are passed as immediate values and the bug cannot
happen.
This got introduced when Daniel reworked the FIQ handling and was
technically always broken, but happened to work with both clang and gcc
before gcc-10 as long as they picked one of the lower registers.
This is probably an indication that still very few people build the
kernel in Thumb2 mode.
Marek pointed out the problem on IRC, Arnd narrowed it down to this
inline assembly and Russell pinpointed the exact bug.
Change the constraints to force the final mode switch to use a non-banked
register for the argument to ensure that the correct constant gets loaded.
Another alternative would be to always use registers for the constant
arguments to avoid the #ifdef that has now become more complex.
Cc: <stable@vger.kernel.org> # v3.18+
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Reported-by: Marek Vasut <marek.vasut@gmail.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Fixes: c0e7f7ee71 ("ARM: 8150/3: fiq: Replace default FIQ handler")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 57ac51667d ]
On Qualcomm ARM32 platforms, the SMC call can return before it has
completed. If this occurs, the call can be restarted, but it requires
using the returned session ID value from the interrupted SMC call.
The ARM32 SMCC code already has the provision to add platform specific
quirks for things like this. So let's make use of it and add the
Qualcomm specific quirk (ARM_SMCCC_QUIRK_QCOM_A6) used by the QCOM_SCM
driver.
This change is similar to the below one added for ARM64 a while ago:
commit 82bcd08702 ("firmware: qcom: scm: Fix interrupted SCM calls")
Without this change, the Qualcomm ARM32 platforms like SDX55 will return
-EINVAL for SMC calls used for modem firmware loading and validation.
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8252ca87c7 ]
Enabling function_graph tracer on ARM causes kernel panic, because the
function graph tracer updates the "return address" of a function in order
to insert a trace callback on function exit, it saves the function's
original return address in a return trace stack, but cpu_suspend() may not
return through the normal return path.
cpu_suspend() will resume directly via the cpu_resume path, but the return
trace stack has been set-up by the subfunctions of cpu_suspend(), which
makes the "return address" inconsistent with cpu_suspend().
This patch refers to Commit de818bd452
("arm64: kernel: pause/unpause function graph tracer in cpu_suspend()"),
fixes the issue by pausing/resuming the function graph tracer on the thread
executing cpu_suspend(), so that the function graph tracer state is kept
consistent across functions that enter power down states and never return
by effectively disabling graph tracer while they are executing.
Signed-off-by: louis.wang <liang26812@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 10fce53c0e upstream
The early ATAGS/DT mapping code uses SECTION_SHIFT to mask low order
bits of R2, and decides that no ATAGS/DTB were provided if the resulting
value is 0x0.
This means that on systems where DRAM starts at 0x0 (such as Raspberry
Pi), no explicit mapping of the DT will be created if R2 points into the
first 1 MB section of memory. This was not a problem before, because the
decompressed kernel is loaded at the base of DRAM and mapped using
sections as well, and so as long as the DT is referenced via a virtual
address that uses the same translation (the linear map, in this case),
things work fine.
However, commit 7a1be318f5 ("9012/1: move device tree mapping out of
linear region") changes this, and now the DT is referenced via a virtual
address that is disjoint from the linear mapping of DRAM, and so we need
the early code to create the DT mapping unconditionally.
So let's create the early DT mapping for any value of R2 != 0x0.
Reported-by: "kernelci.org bot" <bot@kernelci.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fc2933c133 upstream
Commit
149a3ffe62b9dbc3 ("9012/1: move device tree mapping out of linear region")
created a permanent, read-only section mapping of the device tree blob
provided by the firmware, and added a set of macros to get the base and
size of the virtually mapped FDT based on the physical address. However,
while the mapping code uses the SECTION_SIZE macro correctly, the macros
use PMD_SIZE instead, which means something entirely different on ARM when
using short descriptors, and is therefore not the right quantity to use
here. So replace PMD_SIZE with SECTION_SIZE. While at it, change the names
of the macro and its parameter to clarify that it returns the virtual
address of the start of the FDT, based on the physical address in memory.
Tested-by: Joel Stanley <joel@jms.id.au>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7a1be318f5 upstream
On ARM, setting up the linear region is tricky, given the constraints
around placement and alignment of the memblocks, and how the kernel
itself as well as the DT are placed in physical memory.
Let's simplify matters a bit, by moving the device tree mapping to the
top of the address space, right between the end of the vmalloc region
and the start of the the fixmap region, and create a read-only mapping
for it that is independent of the size of the linear region, and how it
is organized.
Since this region was formerly used as a guard region, which will now be
populated fully on LPAE builds by this read-only mapping (which will
still be able to function as a guard region for stray writes), bump the
start of the [underutilized] fixmap region by 512 KB as well, to ensure
that there is always a proper guard region here. Doing so still leaves
ample room for the fixmap space, even with NR_CPUS set to its maximum
value of 32.
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
