linux.git/arch/arm64/kernel, branch v5.1 Linux kernel source tree arm64/module: ftrace: deal with place relative nature of PLTs 2019-04-23T12:35:00+00:00 Ard Biesheuvel ard.biesheuvel@linaro.org 2019-04-13T06:59:25+00:00 4e69ecf4da1ee0b2ac735e1f1bb13935acd5a38d Another bodge for the ftrace PLT code: plt_entries_equal() now takes the place relative nature of the ADRP/ADD based PLT entries into account, which means that a struct trampoline instance on the stack is no longer equal to the same set of opcodes in the module struct, given that they don't point to the same place in memory anymore. Work around this by using memcmp() in the ftrace PLT handling code. Acked-by: Will Deacon <will.deacon@arm.com> Tested-by: dann frazier <dann.frazier@canonical.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 
Another bodge for the ftrace PLT code: plt_entries_equal() now takes
the place relative nature of the ADRP/ADD based PLT entries into
account, which means that a struct trampoline instance on the stack
is no longer equal to the same set of opcodes in the module struct,
given that they don't point to the same place in memory anymore.

Work around this by using memcmp() in the ftrace PLT handling code.

Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: dann frazier <dann.frazier@canonical.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: backtrace: Don't bother trying to unwind the userspace stack 2019-04-08T17:05:24+00:00 Will Deacon will.deacon@arm.com 2019-04-08T16:56:34+00:00 1e6f5440a6814d28c32d347f338bfef68bc3e69d Calling dump_backtrace() with a pt_regs argument corresponding to userspace doesn't make any sense and our unwinder will simply print "Call trace:" before unwinding the stack looking for user frames. Rather than go through this song and dance, just return early if we're passed a user register state. Cc: <stable@vger.kernel.org> Fixes: 1149aad10b1e ("arm64: Add dump_backtrace() in show_regs") Reported-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Will Deacon <will.deacon@arm.com> 
Calling dump_backtrace() with a pt_regs argument corresponding to
userspace doesn't make any sense and our unwinder will simply print
"Call trace:" before unwinding the stack looking for user frames.

Rather than go through this song and dance, just return early if we're
passed a user register state.

Cc: <stable@vger.kernel.org>
Fixes: 1149aad10b1e ("arm64: Add dump_backtrace() in show_regs")
Reported-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
arm64/ftrace: fix inadvertent BUG() in trampoline check 2019-04-08T15:58:13+00:00 Ard Biesheuvel ard.biesheuvel@linaro.org 2019-04-07T19:06:16+00:00 5a3ae7b314a2259b1188b22b392f5eba01e443ee The ftrace trampoline code (which deals with modules loaded out of BL range of the core kernel) uses plt_entries_equal() to check whether the per-module trampoline equals a zero buffer, to decide whether the trampoline has already been initialized. This triggers a BUG() in the opcode manipulation code, since we end up checking the ADRP offset of a 0x0 opcode, which is not an ADRP instruction. So instead, add a helper to check whether a PLT is initialized, and call that from the frace code. Cc: <stable@vger.kernel.org> # v5.0 Fixes: bdb85cd1d206 ("arm64/module: switch to ADRP/ADD sequences for PLT entries") Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> 
The ftrace trampoline code (which deals with modules loaded out of
BL range of the core kernel) uses plt_entries_equal() to check whether
the per-module trampoline equals a zero buffer, to decide whether the
trampoline has already been initialized.

This triggers a BUG() in the opcode manipulation code, since we end
up checking the ADRP offset of a 0x0 opcode, which is not an ADRP
instruction.

So instead, add a helper to check whether a PLT is initialized, and
call that from the frace code.

Cc: <stable@vger.kernel.org> # v5.0
Fixes: bdb85cd1d206 ("arm64/module: switch to ADRP/ADD sequences for PLT entries")
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
arm64: fix wrong check of on_sdei_stack in nmi context 2019-04-04T15:02:25+00:00 Wei Li liwei391@huawei.com 2019-04-01T03:55:57+00:00 1c41860864c8ae0387ef7d44f0000e99cbb2e06d When doing unwind_frame() in the context of pseudo nmi (need enable CONFIG_ARM64_PSEUDO_NMI), reaching the bottom of the stack (fp == 0, pc != 0), function on_sdei_stack() will return true while the sdei acpi table is not inited in fact. This will cause a "NULL pointer dereference" oops when going on. Reviewed-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Wei Li <liwei391@huawei.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 
When doing unwind_frame() in the context of pseudo nmi (need enable
CONFIG_ARM64_PSEUDO_NMI), reaching the bottom of the stack (fp == 0,
pc != 0), function on_sdei_stack() will return true while the sdei acpi
table is not inited in fact. This will cause a "NULL pointer dereference"
oops when going on.

Reviewed-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Wei Li <liwei391@huawei.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: replace memblock_alloc_low with memblock_alloc 2019-03-27T18:12:41+00:00 Chen Zhou chenzhou10@huawei.com 2019-03-27T13:51:16+00:00 9e0a17db517d83d568bb7fa983b54759d4e34f1f If we use "crashkernel=Y[@X]" and the start address is above 4G, the arm64 kdump capture kernel may call memblock_alloc_low() failure in request_standard_resources(). Replacing memblock_alloc_low() with memblock_alloc(). [ 0.000000] MEMBLOCK configuration: [ 0.000000] memory size = 0x0000000040650000 reserved size = 0x0000000004db7f39 [ 0.000000] memory.cnt = 0x6 [ 0.000000] memory[0x0] [0x00000000395f0000-0x000000003968ffff], 0x00000000000a0000 bytes on node 0 flags: 0x4 [ 0.000000] memory[0x1] [0x0000000039730000-0x000000003973ffff], 0x0000000000010000 bytes on node 0 flags: 0x4 [ 0.000000] memory[0x2] [0x0000000039780000-0x000000003986ffff], 0x00000000000f0000 bytes on node 0 flags: 0x4 [ 0.000000] memory[0x3] [0x0000000039890000-0x0000000039d0ffff], 0x0000000000480000 bytes on node 0 flags: 0x4 [ 0.000000] memory[0x4] [0x000000003ed00000-0x000000003ed2ffff], 0x0000000000030000 bytes on node 0 flags: 0x4 [ 0.000000] memory[0x5] [0x0000002040000000-0x000000207fffffff], 0x0000000040000000 bytes on node 0 flags: 0x0 [ 0.000000] reserved.cnt = 0x7 [ 0.000000] reserved[0x0] [0x0000002040080000-0x0000002041c4dfff], 0x0000000001bce000 bytes flags: 0x0 [ 0.000000] reserved[0x1] [0x0000002041c53000-0x0000002042c203f8], 0x0000000000fcd3f9 bytes flags: 0x0 [ 0.000000] reserved[0x2] [0x000000207da00000-0x000000207dbfffff], 0x0000000000200000 bytes flags: 0x0 [ 0.000000] reserved[0x3] [0x000000207ddef000-0x000000207fbfffff], 0x0000000001e11000 bytes flags: 0x0 [ 0.000000] reserved[0x4] [0x000000207fdf2b00-0x000000207fdfc03f], 0x0000000000009540 bytes flags: 0x0 [ 0.000000] reserved[0x5] [0x000000207fdfd000-0x000000207ffff3ff], 0x0000000000202400 bytes flags: 0x0 [ 0.000000] reserved[0x6] [0x000000207ffffe00-0x000000207fffffff], 0x0000000000000200 bytes flags: 0x0 [ 0.000000] Kernel panic - not syncing: request_standard_resources: Failed to allocate 384 bytes [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 5.1.0-next-20190321+ #4 [ 0.000000] Call trace: [ 0.000000] dump_backtrace+0x0/0x188 [ 0.000000] show_stack+0x24/0x30 [ 0.000000] dump_stack+0xa8/0xcc [ 0.000000] panic+0x14c/0x31c [ 0.000000] setup_arch+0x2b0/0x5e0 [ 0.000000] start_kernel+0x90/0x52c [ 0.000000] ---[ end Kernel panic - not syncing: request_standard_resources: Failed to allocate 384 bytes ]--- Link: https://www.spinics.net/lists/arm-kernel/msg715293.html Signed-off-by: Chen Zhou <chenzhou10@huawei.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 
If we use "crashkernel=Y[@X]" and the start address is above 4G,
the arm64 kdump capture kernel may call memblock_alloc_low() failure
in request_standard_resources(). Replacing memblock_alloc_low() with
memblock_alloc().

[    0.000000] MEMBLOCK configuration:
[    0.000000]  memory size = 0x0000000040650000 reserved size = 0x0000000004db7f39
[    0.000000]  memory.cnt  = 0x6
[    0.000000]  memory[0x0]	[0x00000000395f0000-0x000000003968ffff], 0x00000000000a0000 bytes on node 0 flags: 0x4
[    0.000000]  memory[0x1]	[0x0000000039730000-0x000000003973ffff], 0x0000000000010000 bytes on node 0 flags: 0x4
[    0.000000]  memory[0x2]	[0x0000000039780000-0x000000003986ffff], 0x00000000000f0000 bytes on node 0 flags: 0x4
[    0.000000]  memory[0x3]	[0x0000000039890000-0x0000000039d0ffff], 0x0000000000480000 bytes on node 0 flags: 0x4
[    0.000000]  memory[0x4]	[0x000000003ed00000-0x000000003ed2ffff], 0x0000000000030000 bytes on node 0 flags: 0x4
[    0.000000]  memory[0x5]	[0x0000002040000000-0x000000207fffffff], 0x0000000040000000 bytes on node 0 flags: 0x0
[    0.000000]  reserved.cnt  = 0x7
[    0.000000]  reserved[0x0]	[0x0000002040080000-0x0000002041c4dfff], 0x0000000001bce000 bytes flags: 0x0
[    0.000000]  reserved[0x1]	[0x0000002041c53000-0x0000002042c203f8], 0x0000000000fcd3f9 bytes flags: 0x0
[    0.000000]  reserved[0x2]	[0x000000207da00000-0x000000207dbfffff], 0x0000000000200000 bytes flags: 0x0
[    0.000000]  reserved[0x3]	[0x000000207ddef000-0x000000207fbfffff], 0x0000000001e11000 bytes flags: 0x0
[    0.000000]  reserved[0x4]	[0x000000207fdf2b00-0x000000207fdfc03f], 0x0000000000009540 bytes flags: 0x0
[    0.000000]  reserved[0x5]	[0x000000207fdfd000-0x000000207ffff3ff], 0x0000000000202400 bytes flags: 0x0
[    0.000000]  reserved[0x6]	[0x000000207ffffe00-0x000000207fffffff], 0x0000000000000200 bytes flags: 0x0
[    0.000000] Kernel panic - not syncing: request_standard_resources: Failed to allocate 384 bytes
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 5.1.0-next-20190321+ #4
[    0.000000] Call trace:
[    0.000000]  dump_backtrace+0x0/0x188
[    0.000000]  show_stack+0x24/0x30
[    0.000000]  dump_stack+0xa8/0xcc
[    0.000000]  panic+0x14c/0x31c
[    0.000000]  setup_arch+0x2b0/0x5e0
[    0.000000]  start_kernel+0x90/0x52c
[    0.000000] ---[ end Kernel panic - not syncing: request_standard_resources: Failed to allocate 384 bytes ]---

Link: https://www.spinics.net/lists/arm-kernel/msg715293.html
Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: kpti: Whitelist HiSilicon Taishan v110 CPUs 2019-03-19T14:55:10+00:00 Hanjun Guo hanjun.guo@linaro.org 2019-03-05T13:40:58+00:00 0ecc471a2cb7d4d386089445a727f47b59dc9b6e HiSilicon Taishan v110 CPUs didn't implement CSV3 field of the ID_AA64PFR0_EL1 and are not susceptible to Meltdown, so whitelist the MIDR in kpti_safe_list[] table. Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org> Reviewed-by: John Garry <john.garry@huawei.com> Reviewed-by: Zhangshaokun <zhangshaokun@hisilicon.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 
HiSilicon Taishan v110 CPUs didn't implement CSV3 field of the
ID_AA64PFR0_EL1 and are not susceptible to Meltdown, so whitelist
the MIDR in kpti_safe_list[] table.

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Reviewed-by: John Garry <john.garry@huawei.com>
Reviewed-by: Zhangshaokun <zhangshaokun@hisilicon.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64/stacktrace: Export save_stack_trace_regs() 2019-03-19T14:55:10+00:00 William Cohen wcohen@redhat.com 2019-03-01T20:00:41+00:00 c82fd1e6bd55ecc001e610e5484e292a7d8a39fc The ARM64 implements the save_stack_trace_regs function, but it is unusable for any diagnostic tooling compiled as a kernel module due the missing EXPORT_SYMBOL_GPL for the function. Export save_stack_trace_regs() to align with other architectures such as s390, openrisc, and powerpc. This is similar to the ARM64 export of save_stack_trace_tsk() added in git commit e27c7fa015d6. Signed-off-by: William Cohen <wcohen@redhat.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 
The ARM64 implements the save_stack_trace_regs function, but it is
unusable for any diagnostic tooling compiled as a kernel module due
the missing EXPORT_SYMBOL_GPL for the function.  Export
save_stack_trace_regs() to align with other architectures such as
s390, openrisc, and powerpc. This is similar to the ARM64 export of
save_stack_trace_tsk() added in git commit e27c7fa015d6.

Signed-off-by: William Cohen <wcohen@redhat.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: kprobes: Use arch_populate_kprobe_blacklist() 2019-03-19T12:47:44+00:00 Masami Hiramatsu mhiramat@kernel.org 2019-02-12T15:44:48+00:00 6a019a92aa580cd5abdaae578a2a297c9af80174 Use arch_populate_kprobe_blacklist() instead of arch_within_kprobe_blacklist() so that we can see the full blacklisted symbols under the debugfs. Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> [catalin.marinas@arm.com: Add arch_populate_kprobe_blacklist() comment] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 
Use arch_populate_kprobe_blacklist() instead of
arch_within_kprobe_blacklist() so that we can see the full
blacklisted symbols under the debugfs.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
[catalin.marinas@arm.com: Add arch_populate_kprobe_blacklist() comment]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: kprobes: Move exception_text check in blacklist 2019-03-19T12:43:24+00:00 Masami Hiramatsu mhiramat@kernel.org 2019-02-12T15:44:19+00:00 6e08af0f10dcde01f0bdcc64cf91fea9d25e77cc Move exception/irqentry text address check in blacklist, since those are symbol based rejection. If we prohibit probing on the symbols in exception_text, those should be blacklisted. Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 
Move exception/irqentry text address check in blacklist,
since those are symbol based rejection.

If we prohibit probing on the symbols in exception_text,
those should be blacklisted.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: kprobes: Remove unneeded RODATA check 2019-03-19T12:43:09+00:00 Masami Hiramatsu mhiramat@kernel.org 2019-02-12T15:43:51+00:00 b5586163de1ce90317cd4037f69b14105be9f656 Remove unneeded RODATA check from arch_prepare_kprobe(). Since check_kprobe_address_safe() already ensured that the probe address is in kernel text, we don't need to check whether the address in RODATA or not. That must be always false. Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 
Remove unneeded RODATA check from arch_prepare_kprobe().

Since check_kprobe_address_safe() already ensured that
the probe address is in kernel text, we don't need to
check whether the address in RODATA or not. That must
be always false.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>