commit 58aec91efb93338d1cc7acc0a93242613a2a4e5f upstream.
dma-direct.h is introduced in commit d4b6f1562a ("LoongArch: Add
Non-Uniform Memory Access (NUMA) support"). In commit c78c43fe7d
("LoongArch: Use acpi_arch_dma_setup() and remove ARCH_HAS_PHYS_TO_DMA"),
ARCH_HAS_PHYS_TO_DMA was deselected and the coresponding phys_to_dma()/
dma_to_phys() functions were removed. However, the unused dma-direct.h
was left behind, which is removed by this patch.
Cc: <stable@vger.kernel.org>
Fixes: c78c43fe7d ("LoongArch: Use acpi_arch_dma_setup() and remove ARCH_HAS_PHYS_TO_DMA")
Signed-off-by: Miao Wang <shankerwangmiao@gmail.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7697a0fe0154468f5df35c23ebd7aa48994c2cdc upstream.
Chromium sandbox apparently wants to deny statx [1] so it could properly
inspect arguments after the sandboxed process later falls back to fstat.
Because there's currently not a "fd-only" version of statx, so that the
sandbox has no way to ensure the path argument is empty without being
able to peek into the sandboxed process's memory. For architectures able
to do newfstatat though, glibc falls back to newfstatat after getting
-ENOSYS for statx, then the respective SIGSYS handler [2] takes care of
inspecting the path argument, transforming allowed newfstatat's into
fstat instead which is allowed and has the same type of return value.
But, as LoongArch is the first architecture to not have fstat nor
newfstatat, the LoongArch glibc does not attempt falling back at all
when it gets -ENOSYS for statx -- and you see the problem there!
Actually, back when the LoongArch port was under review, people were
aware of the same problem with sandboxing clone3 [3], so clone was
eventually kept. Unfortunately it seemed at that time no one had noticed
statx, so besides restoring fstat/newfstatat to LoongArch uapi (and
postponing the problem further), it seems inevitable that we would need
to tackle seccomp deep argument inspection.
However, this is obviously a decision that shouldn't be taken lightly,
so we just restore fstat/newfstatat by defining __ARCH_WANT_NEW_STAT
in unistd.h. This is the simplest solution for now, and so we hope the
community will tackle the long-standing problem of seccomp deep argument
inspection in the future [4][5].
Also add "newstat" to syscall_abis_64 in Makefile.syscalls due to
upstream asm-generic changes.
More infomation please reading this thread [6].
[1] https://chromium-review.googlesource.com/c/chromium/src/+/2823150
[2] https://chromium.googlesource.com/chromium/src/sandbox/+/c085b51940bd/linux/seccomp-bpf-helpers/sigsys_handlers.cc#355
[3] https://lore.kernel.org/linux-arch/20220511211231.GG7074@brightrain.aerifal.cx/
[4] https://lwn.net/Articles/799557/
[5] https://lpc.events/event/4/contributions/560/attachments/397/640/deep-arg-inspection.pdf
[6] https://lore.kernel.org/loongarch/20240226-granit-seilschaft-eccc2433014d@brauner/T/#t
Cc: stable@vger.kernel.org
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e688c220732e518c2eb1639e9ef77d4a9311713c upstream.
efi_shutdown_init() can register a general sys_off handler named
efi_power_off(). Enable this by providing efi_poweroff_required(),
like arm and x86. Since EFI poweroff is also supported on LoongArch,
and the enablement makes the poweroff function usable for hardwares
which lack ACPI S5.
We prefer ACPI poweroff rather than EFI poweroff (like x86), so we only
require EFI poweroff if acpi_gbl_reduced_hardware or acpi_no_s5 is true.
Cc: stable@vger.kernel.org
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Miao Wang <shankerwangmiao@gmail.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3892b11eac5aaaeefbf717f1953288b77759d9e2 ]
Currently, there are some places to set CSR.PRMD.PWE, the first one is
in hw_breakpoint_thread_switch() to enable user space singlestep via
checking TIF_SINGLESTEP, the second one is in hw_breakpoint_control() to
enable user space watchpoint. For the latter case, it should also check
TIF_LOAD_WATCH to make the logic correct and clear.
Fixes: c8e57ab0995c ("LoongArch: Trigger user-space watchpoints correctly")
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This reverts commit 08f6c05feb which is
commit e60adf513275c3a38e5cb67f7fd12387e43a3ff5 upstream.
It is part of a series that is reported to both break the arm64 builds
and instantly crashes the powerpc systems at the first load of a bpf
program. So revert it for now until it can come back in a safe way.
Reported-by: matoro <matoro_mailinglist_kernel@matoro.tk>
Reported-by: Vitaly Chikunov <vt@altlinux.org>
Reported-by: WangYuli <wangyuli@uniontech.com>
Link: https://lore.kernel.org/r/5A29E00D83AB84E3+20240706031101.637601-1-wangyuli@uniontech.com
Link: https://lore.kernel.org/r/cf736c5e37489e7dc7ffd67b9de2ab47@matoro.tk
Cc: Hari Bathini <hbathini@linux.ibm.com>
Cc: Song Liu <song@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Kees Cook <keescook@chromium.org>
Cc: Puranjay Mohan <puranjay12@gmail.com>
Cc: Ilya Leoshkevich <iii@linux.ibm.com> # s390x
Cc: Tiezhu Yang <yangtiezhu@loongson.cn> # LoongArch
Cc: Johan Almbladh <johan.almbladh@anyfinetworks.com> # MIPS Part
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit beb2800074c15362cf9f6c7301120910046d6556 ]
Currently kernel entry in head.S is in DMW address range, firmware is
instructed to jump to this address after loading the kernel image.
However kernel should not make any assumption on firmware's DMW
setting, thus the entry point should be a physical address falls into
direct translation region.
Fix by converting entry address to physical and amend entry calculation
logic in libstub accordingly.
BTW, use ABSOLUTE() to calculate variables to make Clang/LLVM happy.
Cc: stable@vger.kernel.org
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 174a0c565cea74a7811ff79fbee1b70247570ade ]
The use of the 'kernel_offset' variable to position the image file that
has been loaded by UEFI or GRUB is unnecessary, because we can directly
position the loaded image file through using the image_base field of the
efi_loaded_image struct provided by UEFI.
Replace kernel_offset with image_base to position the image file that has
been loaded by UEFI or GRUB.
Signed-off-by: Wang Yao <wangyao@lemote.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Stable-dep-of: beb2800074c1 ("LoongArch: Fix entry point in kernel image header")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8a736ddfc861b2a217c935c2f461a8004add8247 ]
On non-x86 architectures, the screen_info variable is generally only
used for the VGA console where supported, and in some cases the EFI
framebuffer or vga16fb.
Now that we have a definite list of which architectures actually use it
for what, use consistent #ifdef checks so the global variable is only
defined when it is actually used on those architectures.
Loongarch and riscv have no support for vgacon or vga16fb, but
they support EFI firmware, so only that needs to be checked, and the
initialization can be removed because that is handled by EFI.
IA64 has both vgacon and EFI, though EFI apparently never uses
a framebuffer here.
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Khalid Aziz <khalid@gonehiking.org>
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20231009211845.3136536-3-arnd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: beb2800074c1 ("LoongArch: Fix entry point in kernel image header")
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 3eb2a8b23598e90fda43abb0f23cb267bd5018ba upstream.
In the current code, if multiple hardware breakpoints/watchpoints in
a user-space thread, some of them will not be triggered.
When debugging the following code using gdb.
lihui@bogon:~$ cat test.c
#include <stdio.h>
int a = 0;
int main()
{
printf("start test\n");
a = 1;
printf("a = %d\n", a);
printf("end test\n");
return 0;
}
lihui@bogon:~$ gcc -g test.c -o test
lihui@bogon:~$ gdb test
...
(gdb) start
...
Temporary breakpoint 1, main () at test.c:5
5 printf("start test\n");
(gdb) watch a
Hardware watchpoint 2: a
(gdb) hbreak 8
Hardware assisted breakpoint 3 at 0x1200006ec: file test.c, line 8.
(gdb) c
Continuing.
start test
a = 1
Breakpoint 3, main () at test.c:8
8 printf("end test\n");
...
The first hardware watchpoint is not triggered, the root causes are:
1. In hw_breakpoint_control(), The FWPnCFG1.2.4/MWPnCFG1.2.4 register
settings are not distinguished. They should be set based on hardware
watchpoint functions (fetch or load/store operations).
2. In breakpoint_handler() and watchpoint_handler(), it doesn't identify
which watchpoint is triggered. So, all watchpoint-related perf_event
callbacks are called and siginfo is sent to the user space. This will
cause user-space unable to determine which watchpoint is triggered.
The kernel need to identity which watchpoint is triggered via MWPS/
FWPS registers, and then call the corresponding perf event callbacks
to report siginfo to the user-space.
Modify the relevant code to solve above issues.
All changes according to the LoongArch Reference Manual:
https://loongson.github.io/LoongArch-Documentation/LoongArch-Vol1-EN.html#control-and-status-registers-related-to-watchpoints
With this patch:
lihui@bogon:~$ gdb test
...
(gdb) start
...
Temporary breakpoint 1, main () at test.c:5
5 printf("start test\n");
(gdb) watch a
Hardware watchpoint 2: a
(gdb) hbreak 8
Hardware assisted breakpoint 3 at 0x1200006ec: file test.c, line 8.
(gdb) c
Continuing.
start test
Hardware watchpoint 2: a
Old value = 0
New value = 1
main () at test.c:7
7 printf("a = %d\n", a);
(gdb) c
Continuing.
a = 1
Breakpoint 3, main () at test.c:8
8 printf("end test\n");
(gdb) c
Continuing.
end test
[Inferior 1 (process 778) exited normally]
Cc: stable@vger.kernel.org
Signed-off-by: Hui Li <lihui@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c8e57ab0995c5b443d3c81c8a36b588776dcd0c3 upstream.
In the current code, gdb can set the watchpoint successfully through
ptrace interface, but watchpoint will not be triggered.
When debugging the following code using gdb.
lihui@bogon:~$ cat test.c
#include <stdio.h>
int a = 0;
int main()
{
a = 1;
printf("a = %d\n", a);
return 0;
}
lihui@bogon:~$ gcc -g test.c -o test
lihui@bogon:~$ gdb test
...
(gdb) watch a
...
(gdb) r
...
a = 1
[Inferior 1 (process 4650) exited normally]
No watchpoints were triggered, the root causes are:
1. Kernel uses perf_event and hw_breakpoint framework to control
watchpoint, but the perf_event corresponding to watchpoint is
not enabled. So it needs to be enabled according to MWPnCFG3
or FWPnCFG3 PLV bit field in ptrace_hbp_set_ctrl(), and privilege
is set according to the monitored addr in hw_breakpoint_control().
Furthermore, add a judgment in ptrace_hbp_set_addr() to ensure
kernel-space addr cannot be monitored in user mode.
2. The global enable control for all watchpoints is the WE bit of
CSR.CRMD, and hardware sets the value to 0 when an exception is
triggered. When the ERTN instruction is executed to return, the
hardware restores the value of the PWE field of CSR.PRMD here.
So, before a thread containing watchpoints be scheduled, the PWE
field of CSR.PRMD needs to be set to 1. Add this modification in
hw_breakpoint_control().
All changes according to the LoongArch Reference Manual:
https://loongson.github.io/LoongArch-Documentation/LoongArch-Vol1-EN.html#control-and-status-registers-related-to-watchpointshttps://loongson.github.io/LoongArch-Documentation/LoongArch-Vol1-EN.html#basic-control-and-status-registers
With this patch:
lihui@bogon:~$ gdb test
...
(gdb) watch a
Hardware watchpoint 1: a
(gdb) r
...
Hardware watchpoint 1: a
Old value = 0
New value = 1
main () at test.c:6
6 printf("a = %d\n", a);
(gdb) c
Continuing.
a = 1
[Inferior 1 (process 775) exited normally]
Cc: stable@vger.kernel.org
Signed-off-by: Hui Li <lihui@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f63a47b34b140ed1ca39d7e4bd4f1cdc617fc316 upstream.
In the current code, when debugging the following code using gdb,
"invalid argument ..." message will be displayed.
lihui@bogon:~$ cat test.c
#include <stdio.h>
int a = 0;
int main()
{
a = 1;
return 0;
}
lihui@bogon:~$ gcc -g test.c -o test
lihui@bogon:~$ gdb test
...
(gdb) watch a
Hardware watchpoint 1: a
(gdb) r
...
Invalid argument setting hardware debug registers
There are mainly two types of issues.
1. Some incorrect judgment condition existed in user_watch_state
argument parsing, causing -EINVAL to be returned.
When setting up a watchpoint, gdb uses the ptrace interface,
ptrace(PTRACE_SETREGSET, tid, NT_LOONGARCH_HW_WATCH, (void *) &iov)).
Register values in user_watch_state as follows:
addr[0] = 0x0, mask[0] = 0x0, ctrl[0] = 0x0
addr[1] = 0x0, mask[1] = 0x0, ctrl[1] = 0x0
addr[2] = 0x0, mask[2] = 0x0, ctrl[2] = 0x0
addr[3] = 0x0, mask[3] = 0x0, ctrl[3] = 0x0
addr[4] = 0x0, mask[4] = 0x0, ctrl[4] = 0x0
addr[5] = 0x0, mask[5] = 0x0, ctrl[5] = 0x0
addr[6] = 0x0, mask[6] = 0x0, ctrl[6] = 0x0
addr[7] = 0x12000803c, mask[7] = 0x0, ctrl[7] = 0x610
In arch_bp_generic_fields(), return -EINVAL when ctrl.len is
LOONGARCH_BREAKPOINT_LEN_8(0b00). So delete the incorrect judgment here.
In ptrace_hbp_fill_attr_ctrl(), when note_type is NT_LOONGARCH_HW_WATCH
and ctrl[0] == 0x0, if ((type & HW_BREAKPOINT_RW) != type) will return
-EINVAL. Here ctrl.type should be set based on note_type, and unnecessary
judgments can be removed.
2. The watchpoint argument was not set correctly due to unnecessary
offset and alignment_mask.
Modify ptrace_hbp_fill_attr_ctrl() and hw_breakpoint_arch_parse(), which
ensure the watchpont argument is set correctly.
All changes according to the LoongArch Reference Manual:
https://loongson.github.io/LoongArch-Documentation/LoongArch-Vol1-EN.html#control-and-status-registers-related-to-watchpoints
Cc: stable@vger.kernel.org
Signed-off-by: Hui Li <lihui@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 1a7d0890dd4a502a202aaec792a6c04e6e049547 ]
If an error happens in ftrace, ftrace_kill() will prevent disarming
kprobes. Eventually, the ftrace_ops associated with the kprobes will be
freed, yet the kprobes will still be active, and when triggered, they
will use the freed memory, likely resulting in a page fault and panic.
This behavior can be reproduced quite easily, by creating a kprobe and
then triggering a ftrace_kill(). For simplicity, we can simulate an
ftrace error with a kernel module like [1]:
[1]: https://github.com/brenns10/kernel_stuff/tree/master/ftrace_killer
sudo perf probe --add commit_creds
sudo perf trace -e probe:commit_creds
# In another terminal
make
sudo insmod ftrace_killer.ko # calls ftrace_kill(), simulating bug
# Back to perf terminal
# ctrl-c
sudo perf probe --del commit_creds
After a short period, a page fault and panic would occur as the kprobe
continues to execute and uses the freed ftrace_ops. While ftrace_kill()
is supposed to be used only in extreme circumstances, it is invoked in
FTRACE_WARN_ON() and so there are many places where an unexpected bug
could be triggered, yet the system may continue operating, possibly
without the administrator noticing. If ftrace_kill() does not panic the
system, then we should do everything we can to continue operating,
rather than leave a ticking time bomb.
Link: https://lore.kernel.org/all/20240501162956.229427-1-stephen.s.brennan@oracle.com/
Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Guo Ren <guoren@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 1098efd299ffe9c8af818425338c7f6c4f930a98 upstream.
In JUMP_VIRT_ADDR we are performing an or calculation on address value
directly from pcaddi.
This will only work if we are currently running from direct 1:1 mapping
addresses or firmware's DMW is configured exactly same as kernel. Still,
we should not rely on such assumption.
Fix by overriding higher bits in address comes from pcaddi, so we can
get rid of or operator.
Cc: stable@vger.kernel.org
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3de9c42d02a79a5e09bbee7a4421ddc00cfd5c6d upstream.
NUMA enabled kernel on FDT based machine fails to boot because CPUs
are all in NUMA_NO_NODE and mm subsystem won't accept that.
Fix by adding them to default NUMA node at FDT parsing phase and move
numa_add_cpu(0) to a later point.
Cc: stable@vger.kernel.org
Fixes: 88d4d957ed ("LoongArch: Add FDT booting support from efi system table")
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 56769ba4b297a629148eb24d554aef72d1ddfd9e ]
Currently, there is no standard implementation for vdso_install,
leading to various issues:
1. Code duplication
Many architectures duplicate similar code just for copying files
to the install destination.
Some architectures (arm, sparc, x86) create build-id symlinks,
introducing more code duplication.
2. Unintended updates of in-tree build artifacts
The vdso_install rule depends on the vdso files to install.
It may update in-tree build artifacts. This can be problematic,
as explained in commit 19514fc665 ("arm, kbuild: make
"make install" not depend on vmlinux").
3. Broken code in some architectures
Makefile code is often copied from one architecture to another
without proper adaptation.
'make vdso_install' for parisc does not work.
'make vdso_install' for s390 installs vdso64, but not vdso32.
To address these problems, this commit introduces a generic vdso_install
rule.
Architectures that support vdso_install need to define vdso-install-y
in arch/*/Makefile. vdso-install-y lists the files to install.
For example, arch/x86/Makefile looks like this:
vdso-install-$(CONFIG_X86_64) += arch/x86/entry/vdso/vdso64.so.dbg
vdso-install-$(CONFIG_X86_X32_ABI) += arch/x86/entry/vdso/vdsox32.so.dbg
vdso-install-$(CONFIG_X86_32) += arch/x86/entry/vdso/vdso32.so.dbg
vdso-install-$(CONFIG_IA32_EMULATION) += arch/x86/entry/vdso/vdso32.so.dbg
These files will be installed to $(MODLIB)/vdso/ with the .dbg suffix,
if exists, stripped away.
vdso-install-y can optionally take the second field after the colon
separator. This is needed because some architectures install a vdso
file as a different base name.
The following is a snippet from arch/arm64/Makefile.
vdso-install-$(CONFIG_COMPAT_VDSO) += arch/arm64/kernel/vdso32/vdso.so.dbg:vdso32.so
This will rename vdso.so.dbg to vdso32.so during installation. If such
architectures change their implementation so that the base names match,
this workaround will go away.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Sven Schnelle <svens@linux.ibm.com> # s390
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Reviewed-by: Guo Ren <guoren@kernel.org>
Acked-by: Helge Deller <deller@gmx.de> # parisc
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Stable-dep-of: fc2f5f10f9bc ("s390/vdso: Create .build-id links for unstripped vdso files")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d6af2c76399f98444a5b4de96baf4b362d9f102b ]
With commit d3119bc985fb645 ("LoongArch: Fix callchain parse error with
kernel tracepoint events"), perf can parse kernel callchain, but not
complete and sometimes maybe error. The reason is LoongArch's unwinders
(guess, prologue and orc) don't really need fp (i.e., regs[22]), and
they use sp (i.e., regs[3]) as the frame address rather than the current
stack pointer.
Fix that by removing the assignment of regs[22], and instead assign the
__builtin_frame_address(0) to regs[3].
Without fix:
Children Self Command Shared Object Symbol
........ ........ ............. ................. ................
33.91% 33.91% swapper [kernel.vmlinux] [k] __schedule
|
|--33.04%--__schedule
|
--0.87%--__arch_cpu_idle
__schedule
With this fix:
Children Self Command Shared Object Symbol
........ ........ ............. ................. ................
31.16% 31.16% swapper [kernel.vmlinux] [k] __schedule
|
|--20.63%--smpboot_entry
| cpu_startup_entry
| schedule_idle
| __schedule
|
--10.53%--start_kernel
cpu_startup_entry
schedule_idle
__schedule
Fixes: d3119bc985fb645 ("LoongArch: Fix callchain parse error with kernel tracepoint events")
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f3334ebb8a2a1841c2824594dd992e66de19deb2 ]
There is an smp function call named reset_counters() to init PMU
registers of every CPU in PMU initialization state. It requires that all
CPUs are online. However there is an early_initcall() wrapper for the
PMU init funciton init_hw_perf_events(), so that pmu init funciton is
called in do_pre_smp_initcalls() which before function smp_init().
Function reset_counters() cannot work on other CPUs since they haven't
boot up still.
Here replace the wrapper early_initcall() with pure_initcall(), so that
the PMU init function is called after every cpu is online.
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit efb44ff64c95340b06331fc48634b99efc9dd77c upstream.
As with most architectures, allow handling of read faults in VMAs that
have VM_WRITE but without VM_READ (WRITE implies READ).
Otherwise, reading before writing a write-only memory will error while
reading after writing everything is fine.
BTW, move the VM_EXEC judgement before VM_READ/VM_WRITE to make logic a
little clearer.
Cc: stable@vger.kernel.org
Fixes: 09cfefb7fa ("LoongArch: Add memory management")
Signed-off-by: Jiantao Shan <shanjiantao@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit fea1c949f6ca5059e12de00d0483645debc5b206 ]
The LoongArch CRC32 hw acceleration is based on arch/mips/crypto/
crc32-mips.c. While the MIPS code supports both MIPS32 and MIPS64,
but LoongArch32 lacks the CRC instruction. As a result, the line
"len -= sizeof(u32)" is unnecessary.
Removing it can make context code style more unified and improve
code readability.
Cc: stable@vger.kernel.org
Reviewed-by: WANG Xuerui <git@xen0n.name>
Suggested-by: Wentao Guan <guanwentao@uniontech.com>
Signed-off-by: Yuli Wang <wangyuli@uniontech.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9c68ece8b2a5c5ff9b2fcaea923dd73efeb174cd ]
Commit fb24ea52f7 ("drivers: Remove explicit invocations of
mmiowb()") remove all mmiowb() in drivers, but it says:
"NOTE: mmiowb() has only ever guaranteed ordering in conjunction with
spin_unlock(). However, pairing each mmiowb() removal in this patch with
the corresponding call to spin_unlock() is not at all trivial, so there
is a small chance that this change may regress any drivers incorrectly
relying on mmiowb() to order MMIO writes between CPUs using lock-free
synchronisation."
The mmio in radeon_ring_commit() is protected by a mutex rather than a
spinlock, but in the mutex fastpath it behaves similar to spinlock. We
can add mmiowb() calls in the radeon driver but the maintainer says he
doesn't like such a workaround, and radeon is not the only example of
mutex protected mmio.
So we should extend the mmiowb tracking system from spinlock to mutex,
and maybe other locking primitives. This is not easy and error prone, so
we solve it in the architectural code, by simply defining the __io_aw()
hook as mmiowb(). And we no longer need to override queued_spin_unlock()
so use the generic definition.
Without this, we get such an error when run 'glxgears' on weak ordering
architectures such as LoongArch:
radeon 0000:04:00.0: ring 0 stalled for more than 10324msec
radeon 0000:04:00.0: ring 3 stalled for more than 10240msec
radeon 0000:04:00.0: GPU lockup (current fence id 0x000000000001f412 last fence id 0x000000000001f414 on ring 3)
radeon 0000:04:00.0: GPU lockup (current fence id 0x000000000000f940 last fence id 0x000000000000f941 on ring 0)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)
Link: https://lore.kernel.org/dri-devel/29df7e26-d7a8-4f67-b988-44353c4270ac@amd.com/T/#t
Link: https://lore.kernel.org/linux-arch/20240301130532.3953167-1-chenhuacai@loongson.cn/T/#t
Cc: stable@vger.kernel.org
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c87e12e0e8c1241410e758e181ca6bf23efa5b5b ]
From GCC commit 3f13154553f8546a ("df-scan: remove ad-hoc handling of
global regs in asms"), global registers will no longer be forced to add
to the def-use chain. Then current_thread_info(), current_stack_pointer
and __my_cpu_offset may be lifted out of the loop because they are no
longer treated as "volatile variables".
This optimization is still correct for the current_thread_info() and
current_stack_pointer usages because they are associated to a thread.
However it is wrong for __my_cpu_offset because it is associated to a
CPU rather than a thread: if the thread migrates to a different CPU in
the loop, __my_cpu_offset should be changed.
Change __my_cpu_offset definition to treat it as a "volatile variable",
in order to avoid such a mis-optimization.
Cc: stable@vger.kernel.org
Reported-by: Xiaotian Wu <wuxiaotian@loongson.cn>
Reported-by: Miao Wang <shankerwangmiao@gmail.com>
Signed-off-by: Xing Li <lixing@loongson.cn>
Signed-off-by: Hongchen Zhang <zhanghongchen@loongson.cn>
Signed-off-by: Rui Wang <wangrui@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 9fa304b9f8ec440e614af6d35826110c633c4074 upstream.
The unflatten_and_copy_device_tree() function contains a call to
memblock_alloc(). This means that memblock is allocating memory before
any of the reserved memory regions are set aside in the arch_mem_init()
function which calls early_init_fdt_scan_reserved_mem(). Therefore,
there is a possibility for memblock to allocate from any of the
reserved memory regions.
Hence, move the call to early_init_fdt_scan_reserved_mem() to be earlier
in the init sequence, so that the reserved memory regions are set aside
before any allocations are done using memblock.
Cc: stable@vger.kernel.org
Fixes: 88d4d957ed ("LoongArch: Add FDT booting support from efi system table")
Signed-off-by: Oreoluwa Babatunde <quic_obabatun@quicinc.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 6b79ecd084c99b31c8b4d0beda08893716d5558e ]
LoongArch missed the refactoring made by commit 282a181b1a ("seccomp:
Move config option SECCOMP to arch/Kconfig") because LoongArch was not
mainlined at that time.
The 'depends on PROC_FS' statement is stale as described in that commit.
Select HAVE_ARCH_SECCOMP, and remove the duplicated config entry.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 639420e9f6cd9ca074732b17ac450d2518d5937f upstream.
The earlycon parameter is based on fixmap, and fixmap addresses are not
supposed to be shadowed by KASAN. So return the kasan_early_shadow_page
in kasan_mem_to_shadow() if the input address is above FIXADDR_START.
Otherwise earlycon cannot work after kasan_init().
Cc: stable@vger.kernel.org
Fixes: 5aa4ac64e6 ("LoongArch: Add KASAN (Kernel Address Sanitizer) support")
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4356e9f841f7fbb945521cef3577ba394c65f3fc upstream.
We've had issues with gcc and 'asm goto' before, and we created a
'asm_volatile_goto()' macro for that in the past: see commits
3f0116c323 ("compiler/gcc4: Add quirk for 'asm goto' miscompilation
bug") and a9f180345f ("compiler/gcc4: Make quirk for
asm_volatile_goto() unconditional").
Then, much later, we ended up removing the workaround in commit
43c249ea0b ("compiler-gcc.h: remove ancient workaround for gcc PR
58670") because we no longer supported building the kernel with the
affected gcc versions, but we left the macro uses around.
Now, Sean Christopherson reports a new version of a very similar
problem, which is fixed by re-applying that ancient workaround. But the
problem in question is limited to only the 'asm goto with outputs'
cases, so instead of re-introducing the old workaround as-is, let's
rename and limit the workaround to just that much less common case.
It looks like there are at least two separate issues that all hit in
this area:
(a) some versions of gcc don't mark the asm goto as 'volatile' when it
has outputs:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98619https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110420
which is easy to work around by just adding the 'volatile' by hand.
(b) Internal compiler errors:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110422
which are worked around by adding the extra empty 'asm' as a
barrier, as in the original workaround.
but the problem Sean sees may be a third thing since it involves bad
code generation (not an ICE) even with the manually added 'volatile'.
but the same old workaround works for this case, even if this feels a
bit like voodoo programming and may only be hiding the issue.
Reported-and-tested-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/all/20240208220604.140859-1-seanjc@google.com/
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Uros Bizjak <ubizjak@gmail.com>
Cc: Jakub Jelinek <jakub@redhat.com>
Cc: Andrew Pinski <quic_apinski@quicinc.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5056c596c3d1848021a4eaa76ee42f4c05c50346 upstream.
Machines which have more than 8 nodes fail to boot SMP after commit
a2ccf46333d7b2cf96 ("LoongArch/smp: Call rcutree_report_cpu_starting()
earlier"). Because such machines use tlb-based per-cpu base address
rather than dmw-based per-cpu base address, resulting per-cpu variables
can only be accessed after tlb_init(). But rcutree_report_cpu_starting()
is now called before tlb_init() and accesses per-cpu variables indeed.
Since the original patch want to avoid the lockdep warning caused by
page allocation in tlb_init(), we can move rcutree_report_cpu_starting()
to tlb_init() where after tlb exception configuration but before page
allocation.
Fixes: a2ccf46333d7b2cf96 ("LoongArch/smp: Call rcutree_report_cpu_starting() earlier")
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c2396651309eba291c15e32db8fbe44c738b5921 upstream.
There has been a lingering bug in LoongArch Linux systems causing some
GCC tests to intermittently fail (see Closes link). I've made a minimal
reproducer:
zsh% cat measure.s
.align 4
.globl _start
_start:
movfcsr2gr $a0, $fcsr0
bstrpick.w $a0, $a0, 16, 16
beqz $a0, .ok
break 0
.ok:
li.w $a7, 93
syscall 0
zsh% cc mesaure.s -o measure -nostdlib
zsh% echo $((1.0/3))
0.33333333333333331
zsh% while ./measure; do ; done
This while loop should not stop as POSIX is clear that execve must set
fenv to the default, where FCSR should be zero. But in fact it will
just stop after running for a while (normally less than 30 seconds).
Note that "$((1.0/3))" is needed to reproduce this issue because it
raises FE_INVALID and makes fcsr0 non-zero.
The problem is we are currently relying on SET_PERSONALITY2() to reset
current->thread.fpu.fcsr. But SET_PERSONALITY2() is executed before
start_thread which calls lose_fpu(0). We can see if kernel preempt is
enabled, we may switch to another thread after SET_PERSONALITY2() but
before lose_fpu(0). Then bad thing happens: during the thread switch
the value of the fcsr0 register is stored into current->thread.fpu.fcsr,
making it dirty again.
The issue can be fixed by setting current->thread.fpu.fcsr after
lose_fpu(0) because lose_fpu() clears TIF_USEDFPU, then the thread
switch won't touch current->thread.fpu.fcsr.
The only other architecture setting FCSR in SET_PERSONALITY2() is MIPS.
I've ran a similar test on MIPS with mainline kernel and it turns out
MIPS is buggy, too. Anyway MIPS do this for supporting different FP
flavors (NaN encodings, etc.) which do not exist on LoongArch. So for
LoongArch, we can simply remove the current->thread.fpu.fcsr setting
from SET_PERSONALITY2() and do it in start_thread(), after lose_fpu(0).
The while loop failing with the mainline kernel has survived one hour
after this change on LoongArch.
Fixes: 803b0fc5c3 ("LoongArch: Add process management")
Closes: https://github.com/loongson-community/discussions/issues/7
Link: https://lore.kernel.org/linux-mips/7a6aa1bbdbbe2e63ae96ff163fab0349f58f1b9e.camel@xry111.site/
Cc: stable@vger.kernel.org
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 271f2a4a9576b87ed1f8584909d6d270039e52ea ]
The efi_relocate_kernel() may load the PIE kernel to anywhere, the
loaded address may not be equal to link address or
EFI_KIMG_PREFERRED_ADDRESS.
Acked-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Wang Yao <wangyao@lemote.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d6c5f06e46a836e6a70c7cfd95bb38a67d9252ec ]
Currently, we store syscall nr in pt_regs::regs[11] and syscall execve()
accidentally overrides it during its execution:
sys_execve()
-> do_execve()
-> do_execveat_common()
-> bprm_execve()
-> exec_binprm()
-> search_binary_handler()
-> load_elf_binary()
-> ELF_PLAT_INIT()
ELF_PLAT_INIT() reset regs[11] to 0, so in syscall_exit_to_user_mode()
we later get a wrong syscall nr. This breaks tools like execsnoop since
it relies on execve() tracepoints.
Skip pt_regs::regs[11] reset in ELF_PLAT_INIT() to fix the issue.
Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 97ceddbc9404a7d1e2c4049435bff29427d762cc ]
During unwinding, unwind_done() is used as an end condition. Normally it
unwind to the user stack and then set the stack type to unknown, which
is a normal exit. When something unexpected happens in unwind process
and we cannot unwind anymore, we should set the error flag, and also set
the stack type to unknown to indicate that the unwind process can not
continue. The error flag emphasizes that the unwind process produce an
unexpected error. There is no unexpected things when we unwind the PT_REGS
in the top of IRQ stack and find out that is an user mode PT_REGS. Thus,
we should not set error flag and just set stack type to unknown.
Reported-by: Hengqi Chen <hengqi.chen@gmail.com>
Acked-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit eea673e9d5ea994c60b550ffb684413d3759b3f4 ]
For the following assembly code:
.text
.global func
func:
nop
.data
var:
.dword func
When linked with `-pie`, GNU LD populates the `var` variable with the
pre-relocated value of `func`. However, LLVM LLD does not exhibit the
same behavior. This issue also arises with the `kernel_entry` in arch/
loongarch/kernel/head.S:
_head:
.word MZ_MAGIC /* "MZ", MS-DOS header */
.org 0x8
.dword kernel_entry /* Kernel entry point */
The correct kernel entry from the MS-DOS header is crucial for jumping
to vmlinux from zboot. This necessity is why the compressed relocatable
kernel compiled by Clang encounters difficulties in booting.
To address this problem, it is proposed to apply dynamic relocations to
place with `--apply-dynamic-relocs`.
Link: https://github.com/ClangBuiltLinux/linux/issues/1962
Signed-off-by: WANG Rui <wangrui@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d43f37b73468c172bc89ac4824a1511b411f0778 ]
When a cpu is hot-unplugged, it is put in idle state and the function
arch_cpu_idle_dead() is called. The timer interrupt for this processor
should be disabled, otherwise there will be pending timer interrupt for
the unplugged cpu, so that vcpu is prevented from giving up scheduling
when system is running in vm mode.
This patch implements the timer shutdown interface so that the constant
timer will be properly disabled when a CPU is hot-unplugged.
Reviewed-by: WANG Xuerui <git@xen0n.name>
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 19d86a496233731882aea7ec24505ce6641b1c0c ]
Mark {dmw,tlb}_virt_to_page() exports as non-GPL, in order to let
out-of-tree modules (e.g. OpenZFS) be built without errors. Otherwise
we get:
ERROR: modpost: GPL-incompatible module zfs.ko uses GPL-only symbol 'dmw_virt_to_page'
ERROR: modpost: GPL-incompatible module zfs.ko uses GPL-only symbol 'tlb_virt_to_page'
Reported-by: Haowu Ge <gehaowu@bitmoe.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 902d75cdf0cf0a3fb58550089ee519abf12566f5 ]
The kernel parameter 'nokaslr' is handled before start_kernel(), so we
don't need early_param() to mark it technically. But it can cause a boot
warning as follows:
Unknown kernel command line parameters "nokaslr", will be passed to user space.
When we use 'init=/bin/bash', 'nokaslr' which passed to user space will
even cause a kernel panic. So we use early_param() to mark 'nokaslr',
simply print a notice and silence the boot warning (also fix a potential
panic). This logic is similar to RISC-V.
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit aa0cbc1b506b090c3a775b547c693ada108cc0d7 ]
To clarify, the previous version functioned flawlessly. However, it's
worth noting that the LLVM's LoongArch backend currently lacks support
for cross-section label calculations. With this patch, we enable the use
of clang to compile relocatable kernels.
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: WANG Rui <wangrui@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d3ec75bc635cb0cb8185b63293d33a3d1b942d22 ]
A common issue in Makefile is a race in parallel building.
You need to be careful to prevent multiple threads from writing to the
same file simultaneously.
Commit 3939f33450 ("ARM: 8418/1: add boot image dependencies to not
generate invalid images") addressed such a bad scenario.
A similar symptom occurs with the following command:
$ make -j$(nproc) ARCH=loongarch vmlinux.efi vmlinuz.efi
[ snip ]
SORTTAB vmlinux
OBJCOPY arch/loongarch/boot/vmlinux.efi
OBJCOPY arch/loongarch/boot/vmlinux.efi
PAD arch/loongarch/boot/vmlinux.bin
GZIP arch/loongarch/boot/vmlinuz
OBJCOPY arch/loongarch/boot/vmlinuz.o
LD arch/loongarch/boot/vmlinuz.efi.elf
OBJCOPY arch/loongarch/boot/vmlinuz.efi
The log "OBJCOPY arch/loongarch/boot/vmlinux.efi" is displayed twice.
It indicates that two threads simultaneously enter arch/loongarch/boot/
and write to arch/loongarch/boot/vmlinux.efi.
It occasionally leads to a build failure:
$ make -j$(nproc) ARCH=loongarch vmlinux.efi vmlinuz.efi
[ snip ]
SORTTAB vmlinux
OBJCOPY arch/loongarch/boot/vmlinux.efi
PAD arch/loongarch/boot/vmlinux.bin
truncate: Invalid number: ‘arch/loongarch/boot/vmlinux.bin’
make[2]: *** [drivers/firmware/efi/libstub/Makefile.zboot:13:
arch/loongarch/boot/vmlinux.bin] Error 1
make[2]: *** Deleting file 'arch/loongarch/boot/vmlinux.bin'
make[1]: *** [arch/loongarch/Makefile:146: vmlinuz.efi] Error 2
make[1]: *** Waiting for unfinished jobs....
make: *** [Makefile:234: __sub-make] Error 2
vmlinuz.efi depends on vmlinux.efi, but such a dependency is not
specified in arch/loongarch/Makefile.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 71945968d8b128c955204baa33ec03bdd91bdc26 upstream.
A recent change to the optimization pipeline in LLVM reveals some
fragility around the inlining of LoongArch's __percpu functions, which
manifests as a BUILD_BUG() failure:
In file included from kernel/sched/build_policy.c:17:
In file included from include/linux/sched/cputime.h:5:
In file included from include/linux/sched/signal.h:5:
In file included from include/linux/rculist.h:11:
In file included from include/linux/rcupdate.h:26:
In file included from include/linux/irqflags.h:18:
arch/loongarch/include/asm/percpu.h:97:3: error: call to '__compiletime_assert_51' declared with 'error' attribute: BUILD_BUG failed
97 | BUILD_BUG();
| ^
include/linux/build_bug.h:59:21: note: expanded from macro 'BUILD_BUG'
59 | #define BUILD_BUG() BUILD_BUG_ON_MSG(1, "BUILD_BUG failed")
| ^
include/linux/build_bug.h:39:37: note: expanded from macro 'BUILD_BUG_ON_MSG'
39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
| ^
include/linux/compiler_types.h:425:2: note: expanded from macro 'compiletime_assert'
425 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
| ^
include/linux/compiler_types.h:413:2: note: expanded from macro '_compiletime_assert'
413 | __compiletime_assert(condition, msg, prefix, suffix)
| ^
include/linux/compiler_types.h:406:4: note: expanded from macro '__compiletime_assert'
406 | prefix ## suffix(); \
| ^
<scratch space>:86:1: note: expanded from here
86 | __compiletime_assert_51
| ^
1 error generated.
If these functions are not inlined (which the compiler is free to do
even with functions marked with the standard 'inline' keyword), the
BUILD_BUG() in the default case cannot be eliminated since the compiler
cannot prove it is never used, resulting in a build failure due to the
error attribute.
Mark these functions as __always_inline to guarantee inlining so that
the BUILD_BUG() only triggers when the default case genuinely cannot be
eliminated due to an unexpected size.
Cc: <stable@vger.kernel.org>
Closes: https://github.com/ClangBuiltLinux/linux/issues/1955
Fixes: 46859ac8af ("LoongArch: Add multi-processor (SMP) support")
Link: 1a2e77cf9e
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently the code disables WUC only disables it for ioremap_wc(), which
is only used when mapping writecombine pages like ioremap() (mapped to
the kernel space). But for VRAM mapped in TTM/GEM, it is mapped with a
crafted pgprot by the pgprot_writecombine() function, in which case WUC
isn't disabled now.
Disable WUC for pgprot_writecombine() (fallback to SUC) if needed, like
ioremap_wc().
This improves the AMDGPU driver's stability (solves some misrendering)
on Loongson-3A5000/3A6000 machines.
Signed-off-by: Icenowy Zheng <uwu@icenowy.me>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Replace kmap_atomic()/kunmap_atomic() calls with kmap_local_page()/
kunmap_local() in copy_user_highpage() which can be invoked from both
preemptible and atomic context [1].
[1] https://lore.kernel.org/all/20201029222652.302358281@linutronix.de/
Suggested-by: Deepak R Varma <drv@mailo.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Miao Wang
Yuli Wang