Use the simpler min() macro since both values are unsigned and
compatible.
Signed-off-by: Thorsten Blum <[email protected]>
Signed-off-by: Will Deacon <[email protected]>
When arm64 is configured with CONFIG_DEBUG_VIRTUAL=y, a warning is
printed from the patching code because patch_map(), e.g.
| ------------[ cut here ]------------
| WARNING: CPU: 0 PID: 0 at arch/arm64/kernel/patching.c:45 patch_map.constprop.0+0x120/0xd00
| CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted 6.13.0-rc1-00002-ge1a5d6c6be55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 800003c5 (Nzcv DAIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : patch_map.constprop.0+0x120/0xd00
| lr : patch_map.constprop.0+0x120/0xd00
| sp : ffffa9bb312a79a0
| x29: ffffa9bb312a79a0 x28: 0000000000000001 x27: 0000000000000001
| x26: 0000000000000000 x25: 0000000000000000 x24: 00000000000402e8
| x23: ffffa9bb2c94c1c8 x22: ffffa9bb2c94c000 x21: ffffa9bb222e883c
| x20: 0000000000000002 x19: ffffc1ffc100ba40 x18: ffffa9bb2cf0f21c
| x17: 0000000000000006 x16: 0000000000000000 x15: 0000000000000004
| x14: 1ffff5376625b4ac x13: ffff753766a67fb8 x12: ffff753766919cd1
| x11: 0000000000000003 x10: 1ffff5376625b4c3 x9 : 1ffff5376625b4af
| x8 : ffff753766254f0a x7 : 0000000041b58ab3 x6 : ffff753766254f18
| x5 : ffffa9bb312d9bc0 x4 : 0000000000000000 x3 : ffffa9bb29bd90e4
| x2 : 0000000000000002 x1 : ffffa9bb312d9bc0 x0 : 0000000000000000
| Call trace:
| patch_map.constprop.0+0x120/0xd00 (P)
| patch_map.constprop.0+0x120/0xd00 (L)
| __aarch64_insn_write+0xa8/0x120
| aarch64_insn_patch_text_nosync+0x4c/0xb8
| arch_jump_label_transform_queue+0x7c/0x100
| jump_label_update+0x154/0x460
| static_key_enable_cpuslocked+0x1d8/0x280
| static_key_enable+0x2c/0x48
| early_randomize_kstack_offset+0x104/0x168
| do_early_param+0xe4/0x148
| parse_args+0x3a4/0x838
| parse_early_options+0x50/0x68
| parse_early_param+0x58/0xe0
| setup_arch+0x78/0x1f0
| start_kernel+0xa0/0x530
| __primary_switched+0x8c/0xa0
| irq event stamp: 0
| hardirqs last enabled at (0): [<0000000000000000>] 0x0
| hardirqs last disabled at (0): [<0000000000000000>] 0x0
| softirqs last enabled at (0): [<0000000000000000>] 0x0
| softirqs last disabled at (0): [<0000000000000000>] 0x0
| ---[ end trace 0000000000000000 ]---
The warning has been produced since commit:
3e25d5a49f ("asm-generic: add an optional pfn_valid check to page_to_phys")
... which added a pfn_valid() check into page_to_phys(), and at this
point in boot pfn_valid() will always return false because the vmemmap
has not yet been initialized and there are no valid mem_sections yet.
Before that commit, the arithmetic performed by page_to_phys() would
give the expected physical address, though it is somewhat dubious to use
vmemmap addresses before the vmemmap has been initialized.
Aside from kernel image addresses, all executable code should be
allocated from execmem (where all allocations will fall within the
vmalloc area), and so there's no need for the fallback case when
CONFIG_EXECMEM=n.
Simplify patch_map() accordingly, directly converting kernel image
addresses and removing the redundant fallback case.
Fixes: 3e25d5a49f ("asm-generic: add an optional pfn_valid check to page_to_phys")
Signed-off-by: Mark Rutland <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Mike Rapoport <[email protected]>
Cc: Thomas Huth <[email protected]>
Cc: Will Deacon <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Catalin Marinas <[email protected]>
The text_poke API is used to implement functions like memcpy() and
memset() for instruction memory (RO+X). The implementation is similar to
the x86 version.
This will be used by the BPF JIT to write and modify BPF programs. There
could be more users of this in the future.
Signed-off-by: Puranjay Mohan <[email protected]>
Acked-by: Catalin Marinas <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
These patch_text implementations are using stop_machine_cpuslocked
infrastructure with atomic cpu_count. The original idea: When the
master CPU patch_text, the others should wait for it. But current
implementation is using the first CPU as master, which couldn't
guarantee the remaining CPUs are waiting. This patch changes the
last CPU as the master to solve the potential risk.
Fixes: ae16480785 ("arm64: introduce interfaces to hotpatch kernel and module code")
Signed-off-by: Guo Ren <[email protected]>
Signed-off-by: Guo Ren <[email protected]>
Reviewed-by: Catalin Marinas <[email protected]>
Reviewed-by: Masami Hiramatsu <[email protected]>
Cc: <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Will Deacon <[email protected]>
Currently, <asm/insn.h> includes <asm/patching.h>. We intend that
<asm/insn.h> will be usable from userspace, so it doesn't make sense to
include headers for kernel-only features such as the patching routines,
and we'd intended to restrict <asm/insn.h> to instruction encoding
details.
Let's decouple the patching code from <asm/insn.h>, and explicitly
include <asm/patching.h> where it is needed. Since <asm/patching.h>
isn't included from assembly, we can drop the __ASSEMBLY__ guards.
At the same time, sort the kprobes includes so that it's easier to see
what is and isn't incldued.
Signed-off-by: Mark Rutland <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Will Deacon <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Will Deacon <[email protected]>
Files insn.[c|h] containt some functions used for instruction patching.
In order to reuse the instruction encoder/decoder, move the patching
utilities to their own file.
Signed-off-by: Julien Thierry <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[will: Include patching.h in insn.h to fix header mess; add __ASSEMBLY__ guards]
Signed-off-by: Will Deacon <[email protected]>
Signed-off-by: Will Deacon <[email protected]>
Thorsten Blum