kernel.git/arch/loongarch/include, branch linux-6.10.y

Revert "LoongArch: KVM: Invalidate guest steal time address on vCPU reset"

2024-10-04T14:33:29Z

This reverts commit 05969a6944713f159e8f28be2388500174521818 which is commit 4956e07f05e239b274d042618a250c9fa3e92629 upstream. LoongArch's PV steal time support is add after 6.10, so 6.10.y doesn't need this fix. Signed-off-by: Huacai Chen Signed-off-by: Greg Kroah-Hartman

LoongArch: KVM: Invalidate guest steal time address on vCPU reset

2024-09-30T14:29:28Z

[ Upstream commit 4956e07f05e239b274d042618a250c9fa3e92629 ] If ParaVirt steal time feature is enabled, there is a percpu gpa address passed from guest vCPU and host modifies guest memory space with this gpa address. When vCPU is reset normally, it will notify host and invalidate gpa address. However if VM is crashed and VMM reboots VM forcely, the vCPU reboot notification callback will not be called in VM. Host needs invalidate the gpa address, else host will modify guest memory during VM reboots. Here it is invalidated from the vCPU KVM_REG_LOONGARCH_VCPU_RESET ioctl interface. Also funciton kvm_reset_timer() is removed at vCPU reset stage, since SW emulated timer is only used in vCPU block state. When a vCPU is removed from the block waiting queue, kvm_restore_timer() is called and SW timer is cancelled. And the timer register is also cleared at VMM when a vCPU is reset. Signed-off-by: Bibo Mao Signed-off-by: Huacai Chen Signed-off-by: Sasha Levin

LoongArch: Define ARCH_IRQ_INIT_FLAGS as IRQ_NOPROBE

2024-09-30T14:29:28Z

[ Upstream commit 274ea3563e5ab9f468c15bfb9d2492803a66d9be ] Currently we call irq_set_noprobe() in a loop for all IRQs, but indeed it only works for IRQs below NR_IRQS_LEGACY because at init_IRQ() only legacy interrupts have been allocated. Instead, we can define ARCH_IRQ_INIT_FLAGS as IRQ_NOPROBE in asm/hwirq.h and the core will automatically set the flag for all interrupts. Reviewed-by: Thomas Gleixner Signed-off-by: Huacai Chen Signed-off-by: Tianyang Zhang Signed-off-by: Sasha Levin

LoongArch: Use accessors to page table entries instead of direct dereference

2024-09-12T09:13:13Z

commit 4574815abf43e2bf05643e1b3f7a2e5d6df894f0 upstream. As very well explained in commit 20a004e7b017cce282 ("arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables"), an architecture whose page table walker can modify the PTE in parallel must use READ_ONCE()/ WRITE_ONCE() macro to avoid any compiler transformation. So apply that to LoongArch which is such an architecture, in order to avoid potential problems. Similar to commit edf955647269422e ("riscv: Use accessors to page table entries instead of direct dereference"). Signed-off-by: Huacai Chen Signed-off-by: Greg Kroah-Hartman

LoongArch: Remove the unused dma-direct.h

2024-09-04T11:29:55Z

commit 58aec91efb93338d1cc7acc0a93242613a2a4e5f upstream. dma-direct.h is introduced in commit d4b6f1562a3c3284 ("LoongArch: Add Non-Uniform Memory Access (NUMA) support"). In commit c78c43fe7d42524c ("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: Fixes: c78c43fe7d42 ("LoongArch: Use acpi_arch_dma_setup() and remove ARCH_HAS_PHYS_TO_DMA") Signed-off-by: Miao Wang Signed-off-by: Huacai Chen Signed-off-by: Greg Kroah-Hartman

LoongArch: Define __ARCH_WANT_NEW_STAT in unistd.h

2024-08-19T04:05:37Z

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 Signed-off-by: Greg Kroah-Hartman

LoongArch: Trigger user-space watchpoints correctly

2024-06-21T02:18:40Z

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 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-watchpoints https://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 Signed-off-by: Huacai Chen

LoongArch: Fix watchpoint setting error

2024-06-21T02:18:40Z

In the current code, when debugging the following code using gdb, "invalid argument ..." message will be displayed. lihui@bogon:~$ cat test.c #include 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 Signed-off-by: Huacai Chen

LoongArch: Override higher address bits in JUMP_VIRT_ADDR

2024-06-03T07:45:53Z

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 Signed-off-by: Huacai Chen

LoongArch: Add all CPUs enabled by fdt to NUMA node 0

2024-06-03T07:45:53Z

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: 88d4d957edc7 ("LoongArch: Add FDT booting support from efi system table") Signed-off-by: Jiaxun Yang Signed-off-by: Huacai Chen