linux-stable.git/arch, branch v6.6.138 Linux kernel stable tree KVM: x86: Use __DECLARE_FLEX_ARRAY() for UAPI structures with VLAs 2026-04-27T13:23:34+00:00 David Woodhouse dwmw@amazon.co.uk 2026-04-13T14:58:35+00:00 e297bb2c25686c883738a7d60dec5c4db5e37110 [ Upstream commit 2619da73bb2f10d88f7e1087125c40144fdf0987 ] Commit 94dfc73e7cf4 ("treewide: uapi: Replace zero-length arrays with flexible-array members") broke the userspace API for C++. These structures ending in VLAs are typically a *header*, which can be followed by an arbitrary number of entries. Userspace typically creates a larger structure with some non-zero number of entries, for example in QEMU's kvm_arch_get_supported_msr_feature(): struct { struct kvm_msrs info; struct kvm_msr_entry entries[1]; } msr_data = {}; While that works in C, it fails in C++ with an error like: flexible array member 'kvm_msrs::entries' not at end of 'struct msr_data' Fix this by using __DECLARE_FLEX_ARRAY() for the VLA, which uses [0] for C++ compilation. Fixes: 94dfc73e7cf4 ("treewide: uapi: Replace zero-length arrays with flexible-array members") Cc: stable@vger.kernel.org Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Link: https://patch.msgid.link/3abaf6aefd6e5efeff3b860ac38421d9dec908db.camel@infradead.org [sean: tag for stable@] Signed-off-by: Sean Christopherson <seanjc@google.com> [ applied `__DECLARE_FLEX_ARRAY(char, name)` change directly instead of inside missing `#ifdef __KERNEL__` else branch ] Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 2619da73bb2f10d88f7e1087125c40144fdf0987 ]

Commit 94dfc73e7cf4 ("treewide: uapi: Replace zero-length arrays with
flexible-array members") broke the userspace API for C++.

These structures ending in VLAs are typically a *header*, which can be
followed by an arbitrary number of entries. Userspace typically creates
a larger structure with some non-zero number of entries, for example in
QEMU's kvm_arch_get_supported_msr_feature():

    struct {
        struct kvm_msrs info;
        struct kvm_msr_entry entries[1];
    } msr_data = {};

While that works in C, it fails in C++ with an error like:
 flexible array member 'kvm_msrs::entries' not at end of 'struct msr_data'

Fix this by using __DECLARE_FLEX_ARRAY() for the VLA, which uses [0]
for C++ compilation.

Fixes: 94dfc73e7cf4 ("treewide: uapi: Replace zero-length arrays with flexible-array members")
Cc: stable@vger.kernel.org
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Link: https://patch.msgid.link/3abaf6aefd6e5efeff3b860ac38421d9dec908db.camel@infradead.org
[sean: tag for stable@]
Signed-off-by: Sean Christopherson <seanjc@google.com>
[ applied `__DECLARE_FLEX_ARRAY(char, name)` change directly instead of inside missing `#ifdef __KERNEL__` else branch ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
KVM: x86: Use scratch field in MMIO fragment to hold small write values 2026-04-27T13:23:32+00:00 Sean Christopherson seanjc@google.com 2026-02-25T01:20:36+00:00 dc6a6c3db3a4eca7e747cfc46e22c08d016c68f7 commit 0b16e69d17d8c35c5c9d5918bf596c75a44655d3 upstream. When exiting to userspace to service an emulated MMIO write, copy the to-be-written value to a scratch field in the MMIO fragment if the size of the data payload is 8 bytes or less, i.e. can fit in a single chunk, instead of pointing the fragment directly at the source value. This fixes a class of use-after-free bugs that occur when the emulator initiates a write using an on-stack, local variable as the source, the write splits a page boundary, *and* both pages are MMIO pages. Because KVM's ABI only allows for physically contiguous MMIO requests, accesses that split MMIO pages are separated into two fragments, and are sent to userspace one at a time. When KVM attempts to complete userspace MMIO in response to KVM_RUN after the first fragment, KVM will detect the second fragment and generate a second userspace exit, and reference the on-stack variable. The issue is most visible if the second KVM_RUN is performed by a separate task, in which case the stack of the initiating task can show up as truly freed data. ================================================================== BUG: KASAN: use-after-free in complete_emulated_mmio+0x305/0x420 Read of size 1 at addr ffff888009c378d1 by task syz-executor417/984 CPU: 1 PID: 984 Comm: syz-executor417 Not tainted 5.10.0-182.0.0.95.h2627.eulerosv2r13.x86_64 #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014 Call Trace: dump_stack+0xbe/0xfd print_address_description.constprop.0+0x19/0x170 __kasan_report.cold+0x6c/0x84 kasan_report+0x3a/0x50 check_memory_region+0xfd/0x1f0 memcpy+0x20/0x60 complete_emulated_mmio+0x305/0x420 kvm_arch_vcpu_ioctl_run+0x63f/0x6d0 kvm_vcpu_ioctl+0x413/0xb20 __se_sys_ioctl+0x111/0x160 do_syscall_64+0x30/0x40 entry_SYSCALL_64_after_hwframe+0x67/0xd1 RIP: 0033:0x42477d Code: <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007faa8e6890e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004d7338 RCX: 000000000042477d RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005 RBP: 00000000004d7330 R08: 00007fff28d546df R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004d733c R13: 0000000000000000 R14: 000000000040a200 R15: 00007fff28d54720 The buggy address belongs to the page: page:0000000029f6a428 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x9c37 flags: 0xfffffc0000000(node=0|zone=1|lastcpupid=0x1fffff) raw: 000fffffc0000000 0000000000000000 ffffea0000270dc8 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888009c37780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888009c37800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888009c37880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888009c37900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888009c37980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== The bug can also be reproduced with a targeted KVM-Unit-Test by hacking KVM to fill a large on-stack variable in complete_emulated_mmio(), i.e. by overwrite the data value with garbage. Limit the use of the scratch fields to 8-byte or smaller accesses, and to just writes, as larger accesses and reads are not affected thanks to implementation details in the emulator, but add a sanity check to ensure those details don't change in the future. Specifically, KVM never uses on-stack variables for accesses larger that 8 bytes, e.g. uses an operand in the emulator context, and *all* reads are buffered through the mem_read cache. Note! Using the scratch field for reads is not only unnecessary, it's also extremely difficult to handle correctly. As above, KVM buffers all reads through the mem_read cache, and heavily relies on that behavior when re-emulating the instruction after a userspace MMIO read exit. If a read splits a page, the first page is NOT an MMIO page, and the second page IS an MMIO page, then the MMIO fragment needs to point at _just_ the second chunk of the destination, i.e. its position in the mem_read cache. Taking the "obvious" approach of copying the fragment value into the destination when re-emulating the instruction would clobber the first chunk of the destination, i.e. would clobber the data that was read from guest memory. Fixes: f78146b0f923 ("KVM: Fix page-crossing MMIO") Suggested-by: Yashu Zhang <zhangjiaji1@huawei.com> Reported-by: Yashu Zhang <zhangjiaji1@huawei.com> Closes: https://lore.kernel.org/all/369eaaa2b3c1425c85e8477066391bc7@huawei.com Cc: stable@vger.kernel.org Tested-by: Tom Lendacky <thomas.lendacky@gmail.com> Tested-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Link: https://patch.msgid.link/20260225012049.920665-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 0b16e69d17d8c35c5c9d5918bf596c75a44655d3 upstream.

When exiting to userspace to service an emulated MMIO write, copy the
to-be-written value to a scratch field in the MMIO fragment if the size
of the data payload is 8 bytes or less, i.e. can fit in a single chunk,
instead of pointing the fragment directly at the source value.

This fixes a class of use-after-free bugs that occur when the emulator
initiates a write using an on-stack, local variable as the source, the
write splits a page boundary, *and* both pages are MMIO pages.  Because
KVM's ABI only allows for physically contiguous MMIO requests, accesses
that split MMIO pages are separated into two fragments, and are sent to
userspace one at a time.  When KVM attempts to complete userspace MMIO in
response to KVM_RUN after the first fragment, KVM will detect the second
fragment and generate a second userspace exit, and reference the on-stack
variable.

The issue is most visible if the second KVM_RUN is performed by a separate
task, in which case the stack of the initiating task can show up as truly
freed data.

  ==================================================================
  BUG: KASAN: use-after-free in complete_emulated_mmio+0x305/0x420
  Read of size 1 at addr ffff888009c378d1 by task syz-executor417/984

  CPU: 1 PID: 984 Comm: syz-executor417 Not tainted 5.10.0-182.0.0.95.h2627.eulerosv2r13.x86_64 #3
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014 Call Trace:
  dump_stack+0xbe/0xfd
  print_address_description.constprop.0+0x19/0x170
  __kasan_report.cold+0x6c/0x84
  kasan_report+0x3a/0x50
  check_memory_region+0xfd/0x1f0
  memcpy+0x20/0x60
  complete_emulated_mmio+0x305/0x420
  kvm_arch_vcpu_ioctl_run+0x63f/0x6d0
  kvm_vcpu_ioctl+0x413/0xb20
  __se_sys_ioctl+0x111/0x160
  do_syscall_64+0x30/0x40
  entry_SYSCALL_64_after_hwframe+0x67/0xd1
  RIP: 0033:0x42477d
  Code: <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
  RSP: 002b:00007faa8e6890e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  RAX: ffffffffffffffda RBX: 00000000004d7338 RCX: 000000000042477d
  RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005
  RBP: 00000000004d7330 R08: 00007fff28d546df R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004d733c
  R13: 0000000000000000 R14: 000000000040a200 R15: 00007fff28d54720

  The buggy address belongs to the page:
  page:0000000029f6a428 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x9c37
  flags: 0xfffffc0000000(node=0|zone=1|lastcpupid=0x1fffff)
  raw: 000fffffc0000000 0000000000000000 ffffea0000270dc8 0000000000000000
  raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected

  Memory state around the buggy address:
  ffff888009c37780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  ffff888009c37800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  >ffff888009c37880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                   ^
  ffff888009c37900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  ffff888009c37980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  ==================================================================

The bug can also be reproduced with a targeted KVM-Unit-Test by hacking
KVM to fill a large on-stack variable in complete_emulated_mmio(), i.e. by
overwrite the data value with garbage.

Limit the use of the scratch fields to 8-byte or smaller accesses, and to
just writes, as larger accesses and reads are not affected thanks to
implementation details in the emulator, but add a sanity check to ensure
those details don't change in the future.  Specifically, KVM never uses
on-stack variables for accesses larger that 8 bytes, e.g. uses an operand
in the emulator context, and *all* reads are buffered through the mem_read
cache.

Note!  Using the scratch field for reads is not only unnecessary, it's
also extremely difficult to handle correctly.  As above, KVM buffers all
reads through the mem_read cache, and heavily relies on that behavior when
re-emulating the instruction after a userspace MMIO read exit.  If a read
splits a page, the first page is NOT an MMIO page, and the second page IS
an MMIO page, then the MMIO fragment needs to point at _just_ the second
chunk of the destination, i.e. its position in the mem_read cache.  Taking
the "obvious" approach of copying the fragment value into the destination
when re-emulating the instruction would clobber the first chunk of the
destination, i.e. would clobber the data that was read from guest memory.

Fixes: f78146b0f923 ("KVM: Fix page-crossing MMIO")
Suggested-by: Yashu Zhang <zhangjiaji1@huawei.com>
Reported-by: Yashu Zhang <zhangjiaji1@huawei.com>
Closes: https://lore.kernel.org/all/369eaaa2b3c1425c85e8477066391bc7@huawei.com
Cc: stable@vger.kernel.org
Tested-by: Tom Lendacky <thomas.lendacky@gmail.com>
Tested-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Link: https://patch.msgid.link/20260225012049.920665-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
KVM: nVMX: Fold requested virtual interrupt check into has_nested_events() 2026-04-27T13:23:32+00:00 Sean Christopherson seanjc@google.com 2026-04-15T20:23:46+00:00 5afb9356a2e57f8e41c5d15c4cb46e29793ff61a [ Upstream commit 321ef62b0c5f6f57bb8500a2ca5986052675abbf ] Check for a Requested Virtual Interrupt, i.e. a virtual interrupt that is pending delivery, in vmx_has_nested_events() and drop the one-off kvm_x86_ops.guest_apic_has_interrupt() hook. In addition to dropping a superfluous hook, this fixes a bug where KVM would incorrectly treat virtual interrupts _for L2_ as always enabled due to kvm_arch_interrupt_allowed(), by way of vmx_interrupt_blocked(), treating IRQs as enabled if L2 is active and vmcs12 is configured to exit on IRQs, i.e. KVM would treat a virtual interrupt for L2 as a valid wake event based on L1's IRQ blocking status. Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240607172609.3205077-6-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> Cc: Taeyang Lee <0wn@theori.io> [sean: deal with lack of vmx/main.c and vmx/x86_ops.h] Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 321ef62b0c5f6f57bb8500a2ca5986052675abbf ]

Check for a Requested Virtual Interrupt, i.e. a virtual interrupt that is
pending delivery, in vmx_has_nested_events() and drop the one-off
kvm_x86_ops.guest_apic_has_interrupt() hook.

In addition to dropping a superfluous hook, this fixes a bug where KVM
would incorrectly treat virtual interrupts _for L2_ as always enabled due
to kvm_arch_interrupt_allowed(), by way of vmx_interrupt_blocked(),
treating IRQs as enabled if L2 is active and vmcs12 is configured to exit
on IRQs, i.e. KVM would treat a virtual interrupt for L2 as a valid wake
event based on L1's IRQ blocking status.

Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240607172609.3205077-6-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Cc: Taeyang Lee <0wn@theori.io>
[sean: deal with lack of vmx/main.c and vmx/x86_ops.h]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
KVM: SEV: Drop WARN on large size for KVM_MEMORY_ENCRYPT_REG_REGION 2026-04-27T13:23:31+00:00 Sean Christopherson seanjc@google.com 2026-03-13T00:32:58+00:00 b670833749ffd8681361db2bb047c6f2e3075f3a commit 8acffeef5ef720c35e513e322ab08e32683f32f2 upstream. Drop the WARN in sev_pin_memory() on npages overflowing an int, as the WARN is comically trivially to trigger from userspace, e.g. by doing: struct kvm_enc_region range = { .addr = 0, .size = -1ul, }; __vm_ioctl(vm, KVM_MEMORY_ENCRYPT_REG_REGION, &range); Note, the checks in sev_mem_enc_register_region() that presumably exist to verify the incoming address+size are completely worthless, as both "addr" and "size" are u64s and SEV is 64-bit only, i.e. they _can't_ be greater than ULONG_MAX. That wart will be cleaned up in the near future. if (range->addr > ULONG_MAX || range->size > ULONG_MAX) return -EINVAL; Opportunistically add a comment to explain why the code calculates the number of pages the "hard" way, e.g. instead of just shifting @ulen. Fixes: 78824fabc72e ("KVM: SVM: fix svn_pin_memory()'s use of get_user_pages_fast()") Cc: stable@vger.kernel.org Reviewed-by: Liam Merwick <liam.merwick@oracle.com> Tested-by: Liam Merwick <liam.merwick@oracle.com> Link: https://patch.msgid.link/20260313003302.3136111-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 8acffeef5ef720c35e513e322ab08e32683f32f2 upstream.

Drop the WARN in sev_pin_memory() on npages overflowing an int, as the
WARN is comically trivially to trigger from userspace, e.g. by doing:

  struct kvm_enc_region range = {
          .addr = 0,
          .size = -1ul,
  };

  __vm_ioctl(vm, KVM_MEMORY_ENCRYPT_REG_REGION, &range);

Note, the checks in sev_mem_enc_register_region() that presumably exist to
verify the incoming address+size are completely worthless, as both "addr"
and "size" are u64s and SEV is 64-bit only, i.e. they _can't_ be greater
than ULONG_MAX.  That wart will be cleaned up in the near future.

	if (range->addr > ULONG_MAX || range->size > ULONG_MAX)
		return -EINVAL;

Opportunistically add a comment to explain why the code calculates the
number of pages the "hard" way, e.g. instead of just shifting @ulen.

Fixes: 78824fabc72e ("KVM: SVM: fix svn_pin_memory()'s use of get_user_pages_fast()")
Cc: stable@vger.kernel.org
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Tested-by: Liam Merwick <liam.merwick@oracle.com>
Link: https://patch.msgid.link/20260313003302.3136111-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
perf/x86/intel/uncore: Skip discovery table for offline dies 2026-04-27T13:23:29+00:00 Zide Chen zide.chen@intel.com 2026-03-13T17:40:48+00:00 cfab2c817d2e7e0bee98d66850246ce842ed5f18 [ Upstream commit 7b568e9eba2fad89a696f22f0413d44cf4a1f892 ] This warning can be triggered if NUMA is disabled and the system boots with fewer CPUs than the number of CPUs in die 0. WARNING: CPU: 9 PID: 7257 at uncore.c:1157 uncore_pci_pmu_register+0x136/0x160 [intel_uncore] Currently, the discovery table continues to be parsed even if all CPUs in the associated die are offline. This can lead to an array overflow at "pmu->boxes[die] = box" in uncore_pci_pmu_register(), which may trigger the warning above or cause other issues. Fixes: edae1f06c2cd ("perf/x86/intel/uncore: Parse uncore discovery tables") Reported-by: Steve Wahl <steve.wahl@hpe.com> Signed-off-by: Zide Chen <zide.chen@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com> Tested-by: Steve Wahl <steve.wahl@hpe.com> Link: https://patch.msgid.link/20260313174050.171704-3-zide.chen@intel.com Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 7b568e9eba2fad89a696f22f0413d44cf4a1f892 ]

This warning can be triggered if NUMA is disabled and the system
boots with fewer CPUs than the number of CPUs in die 0.

WARNING: CPU: 9 PID: 7257 at uncore.c:1157 uncore_pci_pmu_register+0x136/0x160 [intel_uncore]

Currently, the discovery table continues to be parsed even if all CPUs
in the associated die are offline.  This can lead to an array overflow
at "pmu->boxes[die] = box" in uncore_pci_pmu_register(), which may
trigger the warning above or cause other issues.

Fixes: edae1f06c2cd ("perf/x86/intel/uncore: Parse uncore discovery tables")
Reported-by: Steve Wahl <steve.wahl@hpe.com>
Signed-off-by: Zide Chen <zide.chen@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Tested-by: Steve Wahl <steve.wahl@hpe.com>
Link: https://patch.msgid.link/20260313174050.171704-3-zide.chen@intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
arm64: dts: imx8mq: Set the correct gpu_ahb clock frequency 2026-04-27T13:23:27+00:00 Sebastian Krzyszkowiak sebastian.krzyszkowiak@puri.sm 2026-01-27T23:28:28+00:00 6948caaff66d7f4749ff88a10ddd87206c8efcc8 [ Upstream commit 1f99b5d93d99ca17d50b386a674d0ce1f20932d8 ] According to i.MX 8M Quad Reference Manual, GPU_AHB_CLK_ROOT's maximum frequency is 400MHz. Fixes: 45d2c84eb3a2 ("arm64: dts: imx8mq: add GPU node") Reviewed-by: Frank Li <Frank.Li@nxp.com> Signed-off-by: Sebastian Krzyszkowiak <sebastian.krzyszkowiak@puri.sm> Reviewed-by: Peng Fan <peng.fan@nxp.com> Reviewed-by: Fabio Estevam <festevam@gmail.com> Signed-off-by: Frank Li <Frank.Li@nxp.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 1f99b5d93d99ca17d50b386a674d0ce1f20932d8 ]

According to i.MX 8M Quad Reference Manual, GPU_AHB_CLK_ROOT's maximum
frequency is 400MHz.

Fixes: 45d2c84eb3a2 ("arm64: dts: imx8mq: add GPU node")
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Sebastian Krzyszkowiak <sebastian.krzyszkowiak@puri.sm>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
arm64: dts: hisilicon: hi3798cv200: Add missing dma-ranges 2026-04-18T08:39:51+00:00 Shawn Guo shawnguo@kernel.org 2026-02-27T07:22:10+00:00 0f36273a4b24ad8fb072b5e30387de61d1d99fcf commit 1af997cad473d505248df6d9577183bb91f69670 upstream. Reboot starts failing on Poplar since commit 8424ecdde7df ("arm64: mm: Set ZONE_DMA size based on devicetree's dma-ranges"), which effectively changes zone_dma_bits from 30 to 32 for arm64 platforms that do not properly define dma-ranges in device tree. It's unclear how Poplar reboot gets broken by this change exactly, but a dma-ranges limiting zone_dma to the first 1 GB fixes the regression. Fixes: 2f20182ed670 ("arm64: dts: hisilicon: add dts files for hi3798cv200-poplar board") Cc: stable@vger.kernel.org Signed-off-by: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Wei Xu <xuwei5@hisilicon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 1af997cad473d505248df6d9577183bb91f69670 upstream.

Reboot starts failing on Poplar since commit 8424ecdde7df ("arm64: mm:
Set ZONE_DMA size based on devicetree's dma-ranges"), which effectively
changes zone_dma_bits from 30 to 32 for arm64 platforms that do not
properly define dma-ranges in device tree.  It's unclear how Poplar reboot
gets broken by this change exactly, but a dma-ranges limiting zone_dma to
the first 1 GB fixes the regression.

Fixes: 2f20182ed670 ("arm64: dts: hisilicon: add dts files for hi3798cv200-poplar board")
Cc: stable@vger.kernel.org
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arm64: dts: hisilicon: poplar: Correct PCIe reset GPIO polarity 2026-04-18T08:39:51+00:00 Shawn Guo shawnguo@kernel.org 2026-02-27T07:19:58+00:00 e3d84395a16d8ce2edc233c85bad1043ad606025 commit c1f2b0f2b5e37b2c27540a175aea2755a3799433 upstream. The PCIe reset GPIO on Poplar is actually active low. The active high worked before because kernel driver didn't respect the setting from DT. This is changed since commit 1d26a55fbeb9 ("PCI: histb: Switch to using gpiod API"), and thus PCIe on Poplar got brken since then. Fix the problem by correcting the polarity. Fixes: 32fa01761bd9 ("arm64: dts: hi3798cv200: enable PCIe support for poplar board") Cc: stable@vger.kernel.org Signed-off-by: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Wei Xu <xuwei5@hisilicon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit c1f2b0f2b5e37b2c27540a175aea2755a3799433 upstream.

The PCIe reset GPIO on Poplar is actually active low.  The active high
worked before because kernel driver didn't respect the setting from DT.
This is changed since commit 1d26a55fbeb9 ("PCI: histb: Switch to using
gpiod API"), and thus PCIe on Poplar got brken since then.

Fix the problem by correcting the polarity.

Fixes: 32fa01761bd9 ("arm64: dts: hi3798cv200: enable PCIe support for poplar board")
Cc: stable@vger.kernel.org
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arm64: dts: imx8mq-librem5: Bump BUCK1 suspend voltage up to 0.85V 2026-04-18T08:39:51+00:00 Sebastian Krzyszkowiak sebastian.krzyszkowiak@puri.sm 2026-02-21T18:15:19+00:00 e85ee7bd042cccce6d9d8d87622a508aeb3be3b5 commit 511f76bf1dce5acf8907b65a7d1bc8f7e7c0d637 upstream. The minimal voltage of VDD_SOC sourced from BUCK1 is 0.81V, which is the currently set value. However, BD71837 only guarantees accuracy of ±0.01V, and this still doesn't factor other reasons for actual voltage to slightly drop in, resulting in the possibility of running out of the operational range. Bump the voltage up to 0.85V, which should give enough headroom. Cc: stable@vger.kernel.org Fixes: 8f0216b006e5 ("arm64: dts: Add a device tree for the Librem 5 phone") Signed-off-by: Sebastian Krzyszkowiak <sebastian.krzyszkowiak@puri.sm> Signed-off-by: Frank Li <Frank.Li@nxp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 511f76bf1dce5acf8907b65a7d1bc8f7e7c0d637 upstream.

The minimal voltage of VDD_SOC sourced from BUCK1 is 0.81V, which
is the currently set value. However, BD71837 only guarantees accuracy
of ±0.01V, and this still doesn't factor other reasons for actual
voltage to slightly drop in, resulting in the possibility of running
out of the operational range.

Bump the voltage up to 0.85V, which should give enough headroom.

Cc: stable@vger.kernel.org
Fixes: 8f0216b006e5 ("arm64: dts: Add a device tree for the Librem 5 phone")
Signed-off-by: Sebastian Krzyszkowiak <sebastian.krzyszkowiak@puri.sm>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Revert "arm64: dts: imx8mq-librem5: Set the DVS voltages lower" 2026-04-18T08:39:51+00:00 Sebastian Krzyszkowiak sebastian.krzyszkowiak@puri.sm 2026-02-21T18:15:18+00:00 03c00ef6d6dfd215c446f77eb9be3035833cf5f0 commit 4cd46ea0eb4504f7f4fea92cb4601c5c9a3e545e upstream. This reverts commit c24a9b698fb02cd0723fa8375abab07f94b97b10. It's been found that there's a significant per-unit variance in accepted supply voltages and the current set still makes some units unstable. Revert back to nominal values. Cc: stable@vger.kernel.org Fixes: c24a9b698fb0 ("arm64: dts: imx8mq-librem5: Set the DVS voltages lower") Signed-off-by: Sebastian Krzyszkowiak <sebastian.krzyszkowiak@puri.sm> Signed-off-by: Frank Li <Frank.Li@nxp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 4cd46ea0eb4504f7f4fea92cb4601c5c9a3e545e upstream.

This reverts commit c24a9b698fb02cd0723fa8375abab07f94b97b10.

It's been found that there's a significant per-unit variance in accepted
supply voltages and the current set still makes some units unstable.

Revert back to nominal values.

Cc: stable@vger.kernel.org
Fixes: c24a9b698fb0 ("arm64: dts: imx8mq-librem5: Set the DVS voltages lower")
Signed-off-by: Sebastian Krzyszkowiak <sebastian.krzyszkowiak@puri.sm>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>