Commit Graph

16889 Commits

Author SHA1 Message Date
Ingo Molnar e855e80d00 Linux 5.12-rc5
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Merge tag 'v5.12-rc5' into WIP.x86/core, to pick up recent NOP related changes

In particular we want to have this upstream commit:

  b90829704780: ("bpf: Use NOP_ATOMIC5 instead of emit_nops(&prog, 5) for BPF_TRAMP_F_CALL_ORIG")

... before merging in x86/cpu changes and the removal of the NOP optimizations, and
applying PeterZ's !retpoline objtool series.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2021-04-02 12:33:16 +02:00
Borislav Petkov f2ac256b9a Merge 'x86/alternatives'
Pick up dependent changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
2021-03-31 18:04:19 +02:00
Peter Zijlstra 52fa82c21f x86: Add insn_decode_kernel()
Add a helper to decode kernel instructions; there's no point in
endlessly repeating those last two arguments.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210326151259.379242587@infradead.org
2021-03-31 16:20:22 +02:00
Wei Yongjun 2304d14db6 x86/kprobes: Move 'inline' to the beginning of the kprobe_is_ss() declaration
Address this GCC warning:

  arch/x86/kernel/kprobes/core.c:940:1:
   warning: 'inline' is not at beginning of declaration [-Wold-style-declaration]
    940 | static int nokprobe_inline kprobe_is_ss(struct kprobe_ctlblk *kcb)
        | ^~~~~~

[ mingo: Tidied up the changelog. ]

Fixes: 6256e668b7af: ("x86/kprobes: Use int3 instead of debug trap for single-step")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20210324144502.1154883-1-weiyongjun1@huawei.com
2021-03-25 13:07:58 +01:00
Masami Hiramatsu 2f706e0e5e x86/kprobes: Fix to identify indirect jmp and others using range case
Fix can_boost() to identify indirect jmp and others using range case
correctly.

Since the condition in switch statement is opcode & 0xf0, it can not
evaluate to 0xff case. This should be under the 0xf0 case. However,
there is no reason to use the conbinations of the bit-masked condition
and lower bit checking.

Use range case to clean up the switch statement too.

Fixes: 6256e668b7 ("x86/kprobes: Use int3 instead of debug trap for single-step")
Reported-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/161666692308.1120877.4675552834049546493.stgit@devnote2
2021-03-25 11:37:22 +01:00
Masami Hiramatsu 6dd3b8c9f5 x86/kprobes: Fix to check non boostable prefixes correctly
There are 2 bugs in the can_boost() function because of using
x86 insn decoder. Since the insn->opcode never has a prefix byte,
it can not find CS override prefix in it. And the insn->attr is
the attribute of the opcode, thus inat_is_address_size_prefix(
insn->attr) always returns false.

Fix those by checking each prefix bytes with for_each_insn_prefix
loop and getting the correct attribute for each prefix byte.
Also, this removes unlikely, because this is a slow path.

Fixes: a8d11cd071 ("kprobes/x86: Consolidate insn decoder users for copying code")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/161666691162.1120877.2808435205294352583.stgit@devnote2
2021-03-25 11:37:21 +01:00
Masami Hiramatsu 6256e668b7 x86/kprobes: Use int3 instead of debug trap for single-step
Use int3 instead of debug trap exception for single-stepping the
probed instructions. Some instructions which change the ip
registers or modify IF flags are emulated because those are not
able to be single-stepped by int3 or may allow the interrupt
while single-stepping.

This actually changes the kprobes behavior.

- kprobes can not probe following instructions; int3, iret,
  far jmp/call which get absolute address as immediate,
  indirect far jmp/call, indirect near jmp/call with addressing
  by memory (register-based indirect jmp/call are OK), and
  vmcall/vmlaunch/vmresume/vmxoff.

- If the kprobe post_handler doesn't set before registering,
  it may not be called in some case even if you set it afterwards.
  (IOW, kprobe booster is enabled at registration, user can not
   change it)

But both are rare issue, unsupported instructions will not be
used in the kernel (or rarely used), and post_handlers are
rarely used (I don't see it except for the test code).

Suggested-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/161469874601.49483.11985325887166921076.stgit@devnote2
2021-03-23 16:07:56 +01:00
Masami Hiramatsu a194acd316 x86/kprobes: Identify far indirect JMP correctly
Since Grp5 far indirect JMP is FF "mod 101 r/m", it should be
(modrm & 0x38) == 0x28, and near indirect JMP is also 0x38 == 0x20.
So we can mask modrm with 0x30 and check 0x20.
This is actually what the original code does, it also doesn't care
the last bit. So the result code is same.

Thus, I think this is just a cosmetic cleanup.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/161469873475.49483.13257083019966335137.stgit@devnote2
2021-03-23 16:07:56 +01:00
Masami Hiramatsu d60ad3d46f x86/kprobes: Retrieve correct opcode for group instruction
Since the opcodes start from 0xff are group5 instruction group which is
not 2 bytes opcode but the extended opcode determined by the MOD/RM byte.

The commit abd82e533d ("x86/kprobes: Do not decode opcode in resume_execution()")
used insn->opcode.bytes[1], but that is not correct. We have to refer
the insn->modrm.bytes[1] instead.

Fixes: abd82e533d ("x86/kprobes: Do not decode opcode in resume_execution()")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/161469872400.49483.18214724458034233166.stgit@devnote2
2021-03-23 16:07:55 +01:00
Linus Torvalds 5e3ddf96e7 - Add the arch-specific mapping between physical and logical CPUs to fix
devicetree-node lookups.
 
 - Restore the IRQ2 ignore logic
 
 - Fix get_nr_restart_syscall() to return the correct restart syscall number.
 Split in a 4-patches set to avoid kABI breakage when backporting to dead
 kernels.
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Merge tag 'x86_urgent_for_v5.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Borislav Petkov:
 "The freshest pile of shiny x86 fixes for 5.12:

   - Add the arch-specific mapping between physical and logical CPUs to
     fix devicetree-node lookups

   - Restore the IRQ2 ignore logic

   - Fix get_nr_restart_syscall() to return the correct restart syscall
     number. Split in a 4-patches set to avoid kABI breakage when
     backporting to dead kernels"

* tag 'x86_urgent_for_v5.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/apic/of: Fix CPU devicetree-node lookups
  x86/ioapic: Ignore IRQ2 again
  x86: Introduce restart_block->arch_data to remove TS_COMPAT_RESTART
  x86: Introduce TS_COMPAT_RESTART to fix get_nr_restart_syscall()
  x86: Move TS_COMPAT back to asm/thread_info.h
  kernel, fs: Introduce and use set_restart_fn() and arch_set_restart_data()
2021-03-21 11:04:20 -07:00
Linus Torvalds 812da4d394 RISC-V Fixes for 5.12-rc4
I have handful of fixes for 5.12:
 
 * A fix to the SBI remote fence numbers for hypervisor fences, which had
   been transcribed in the wrong order in Linux.  These fences are only
   used with the KVM patches applied.
 * A whole host of build warnings have been fixed, these should have no
   functional change.
 * A fix to init_resources() that prevents an off-by-one error from
   causing an out-of-bounds array reference.  This is manifesting during
   boot on vexriscv.
 * A fix to ensure the KASAN mappings are visible before proceeding to
   use them.
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Merge tag 'riscv-for-linus-5.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V fixes from Palmer Dabbelt:
 "A handful of fixes for 5.12:

   - fix the SBI remote fence numbers for hypervisor fences, which had
     been transcribed in the wrong order in Linux. These fences are only
     used with the KVM patches applied.

   - fix a whole host of build warnings, these should have no functional
     change.

   - fix init_resources() to prevent an off-by-one error from causing an
     out-of-bounds array reference. This was manifesting during boot on
     vexriscv.

   - ensure the KASAN mappings are visible before proceeding to use
     them"

* tag 'riscv-for-linus-5.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: Correct SPARSEMEM configuration
  RISC-V: kasan: Declare kasan_shallow_populate() static
  riscv: Ensure page table writes are flushed when initializing KASAN vmalloc
  RISC-V: Fix out-of-bounds accesses in init_resources()
  riscv: Fix compilation error with Canaan SoC
  ftrace: Fix spelling mistake "disabed" -> "disabled"
  riscv: fix bugon.cocci warnings
  riscv: process: Fix no prototype for arch_dup_task_struct
  riscv: ftrace: Use ftrace_get_regs helper
  riscv: process: Fix no prototype for show_regs
  riscv: syscall_table: Reduce W=1 compilation warnings noise
  riscv: time: Fix no prototype for time_init
  riscv: ptrace: Fix no prototype warnings
  riscv: sbi: Fix comment of __sbi_set_timer_v01
  riscv: irq: Fix no prototype warning
  riscv: traps: Fix no prototype warnings
  RISC-V: correct enum sbi_ext_rfence_fid
2021-03-20 11:01:54 -07:00
Johan Hovold dd926880da x86/apic/of: Fix CPU devicetree-node lookups
Architectures that describe the CPU topology in devicetree and do not have
an identity mapping between physical and logical CPU ids must override the
default implementation of arch_match_cpu_phys_id().

Failing to do so breaks CPU devicetree-node lookups using of_get_cpu_node()
and of_cpu_device_node_get() which several drivers rely on. It also causes
the CPU struct devices exported through sysfs to point to the wrong
devicetree nodes.

On x86, CPUs are described in devicetree using their APIC ids and those
do not generally coincide with the logical ids, even if CPU0 typically
uses APIC id 0.

Add the missing implementation of arch_match_cpu_phys_id() so that CPU-node
lookups work also with SMP.

Apart from fixing the broken sysfs devicetree-node links this likely does
not affect current users of mainline kernels on x86.

Fixes: 4e07db9c8d ("x86/devicetree: Use CPU description from Device Tree")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210312092033.26317-1-johan@kernel.org
2021-03-19 23:01:49 +01:00
Thomas Gleixner a501b048a9 x86/ioapic: Ignore IRQ2 again
Vitaly ran into an issue with hotplugging CPU0 on an Amazon instance where
the matrix allocator claimed to be out of vectors. He analyzed it down to
the point that IRQ2, the PIC cascade interrupt, which is supposed to be not
ever routed to the IO/APIC ended up having an interrupt vector assigned
which got moved during unplug of CPU0.

The underlying issue is that IRQ2 for various reasons (see commit
af174783b9 ("x86: I/O APIC: Never configure IRQ2" for details) is treated
as a reserved system vector by the vector core code and is not accounted as
a regular vector. The Amazon BIOS has an routing entry of pin2 to IRQ2
which causes the IO/APIC setup to claim that interrupt which is granted by
the vector domain because there is no sanity check. As a consequence the
allocation counter of CPU0 underflows which causes a subsequent unplug to
fail with:

  [ ... ] CPU 0 has 4294967295 vectors, 589 available. Cannot disable CPU

There is another sanity check missing in the matrix allocator, but the
underlying root cause is that the IO/APIC code lost the IRQ2 ignore logic
during the conversion to irqdomains.

For almost 6 years nobody complained about this wreckage, which might
indicate that this requirement could be lifted, but for any system which
actually has a PIC IRQ2 is unusable by design so any routing entry has no
effect and the interrupt cannot be connected to a device anyway.

Due to that and due to history biased paranoia reasons restore the IRQ2
ignore logic and treat it as non existent despite a routing entry claiming
otherwise.

Fixes: d32932d02e ("x86/irq: Convert IOAPIC to use hierarchical irqdomain interfaces")
Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210318192819.636943062@linutronix.de
2021-03-19 12:43:41 +01:00
Wanpeng Li f4e61f0c9a x86/kvm: Fix broken irq restoration in kvm_wait
After commit 997acaf6b4 (lockdep: report broken irq restoration), the guest
splatting below during boot:

 raw_local_irq_restore() called with IRQs enabled
 WARNING: CPU: 1 PID: 169 at kernel/locking/irqflag-debug.c:10 warn_bogus_irq_restore+0x26/0x30
 Modules linked in: hid_generic usbhid hid
 CPU: 1 PID: 169 Comm: systemd-udevd Not tainted 5.11.0+ #25
 RIP: 0010:warn_bogus_irq_restore+0x26/0x30
 Call Trace:
  kvm_wait+0x76/0x90
  __pv_queued_spin_lock_slowpath+0x285/0x2e0
  do_raw_spin_lock+0xc9/0xd0
  _raw_spin_lock+0x59/0x70
  lockref_get_not_dead+0xf/0x50
  __legitimize_path+0x31/0x60
  legitimize_root+0x37/0x50
  try_to_unlazy_next+0x7f/0x1d0
  lookup_fast+0xb0/0x170
  path_openat+0x165/0x9b0
  do_filp_open+0x99/0x110
  do_sys_openat2+0x1f1/0x2e0
  do_sys_open+0x5c/0x80
  __x64_sys_open+0x21/0x30
  do_syscall_64+0x32/0x50
  entry_SYSCALL_64_after_hwframe+0x44/0xae

The new consistency checking,  expects local_irq_save() and
local_irq_restore() to be paired and sanely nested, and therefore expects
local_irq_restore() to be called with irqs disabled.
The irqflags handling in kvm_wait() which ends up doing:

	local_irq_save(flags);
	safe_halt();
	local_irq_restore(flags);

instead triggers it.  This patch fixes it by using
local_irq_disable()/enable() directly.

Cc: Thomas Gleixner <tglx@linutronix.de>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Message-Id: <1615791328-2735-1-git-send-email-wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-18 13:58:14 -04:00
Colin Ian King bab1770a2c
ftrace: Fix spelling mistake "disabed" -> "disabled"
There is a spelling mistake in a comment, fix it.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-03-16 21:19:40 -07:00
Oleg Nesterov b2e9df850c x86: Introduce restart_block->arch_data to remove TS_COMPAT_RESTART
Save the current_thread_info()->status of X86 in the new
restart_block->arch_data field so TS_COMPAT_RESTART can be removed again.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210201174716.GA17898@redhat.com
2021-03-16 22:13:11 +01:00
Oleg Nesterov 8c150ba2fb x86: Introduce TS_COMPAT_RESTART to fix get_nr_restart_syscall()
The comment in get_nr_restart_syscall() says:

	 * The problem is that we can get here when ptrace pokes
	 * syscall-like values into regs even if we're not in a syscall
	 * at all.

Yes, but if not in a syscall then the

	status & (TS_COMPAT|TS_I386_REGS_POKED)

check below can't really help:

	- TS_COMPAT can't be set

	- TS_I386_REGS_POKED is only set if regs->orig_ax was changed by
	  32bit debugger; and even in this case get_nr_restart_syscall()
	  is only correct if the tracee is 32bit too.

Suppose that a 64bit debugger plays with a 32bit tracee and

	* Tracee calls sleep(2)	// TS_COMPAT is set
	* User interrupts the tracee by CTRL-C after 1 sec and does
	  "(gdb) call func()"
	* gdb saves the regs by PTRACE_GETREGS
	* does PTRACE_SETREGS to set %rip='func' and %orig_rax=-1
	* PTRACE_CONT		// TS_COMPAT is cleared
	* func() hits int3.
	* Debugger catches SIGTRAP.
	* Restore original regs by PTRACE_SETREGS.
	* PTRACE_CONT

get_nr_restart_syscall() wrongly returns __NR_restart_syscall==219, the
tracee calls ia32_sys_call_table[219] == sys_madvise.

Add the sticky TS_COMPAT_RESTART flag which survives after return to user
mode. It's going to be removed in the next step again by storing the
information in the restart block. As a further cleanup it might be possible
to remove also TS_I386_REGS_POKED with that.

Test-case:

  $ cvs -d :pserver:anoncvs:anoncvs@sourceware.org:/cvs/systemtap co ptrace-tests
  $ gcc -o erestartsys-trap-debuggee ptrace-tests/tests/erestartsys-trap-debuggee.c --m32
  $ gcc -o erestartsys-trap-debugger ptrace-tests/tests/erestartsys-trap-debugger.c -lutil
  $ ./erestartsys-trap-debugger
  Unexpected: retval 1, errno 22
  erestartsys-trap-debugger: ptrace-tests/tests/erestartsys-trap-debugger.c:421

Fixes: 609c19a385 ("x86/ptrace: Stop setting TS_COMPAT in ptrace code")
Reported-by: Jan Kratochvil <jan.kratochvil@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210201174709.GA17895@redhat.com
2021-03-16 22:13:11 +01:00
Borislav Petkov 88afc23922 x86/uprobes: Convert to insn_decode()
Simplify code, no functional changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210304174237.31945-16-bp@alien8.de
2021-03-15 12:05:03 +01:00
Borislav Petkov 0be7f42d6f x86/traps: Convert to insn_decode()
Simplify code, no functional changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210304174237.31945-15-bp@alien8.de
2021-03-15 12:00:18 +01:00
Borislav Petkov 5e32c64bb6 x86/sev-es: Convert to insn_decode()
Simplify code, no functional changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210304174237.31945-14-bp@alien8.de
2021-03-15 11:46:40 +01:00
Borislav Petkov 99e4b0de4d x86/sev-es: Split vc_decode_insn()
Split it into two helpers - a user- and a kernel-mode one for
readability. Yes, the original function body is not that convoluted but
splitting it makes following through that code trivial than having to
pay attention to each little difference when in user or in kernel mode.

No functional changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210304174237.31945-13-bp@alien8.de
2021-03-15 11:40:05 +01:00
Borislav Petkov 77e768ec13 x86/kprobes: Convert to insn_decode()
Simplify code, improve decoding error checking.

Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lkml.kernel.org/r/20210304174237.31945-12-bp@alien8.de
2021-03-15 11:28:20 +01:00
Borislav Petkov 1580f488ea x86/mce: Convert to insn_decode()
Simplify code, no functional changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210304174237.31945-11-bp@alien8.de
2021-03-15 11:26:40 +01:00
Borislav Petkov 63c66cde7b x86/alternative: Use insn_decode()
No functional changes, just simplification.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210304174237.31945-10-bp@alien8.de
2021-03-15 11:25:38 +01:00
Borislav Petkov 9e761296c5 x86/insn: Rename insn_decode() to insn_decode_from_regs()
Rename insn_decode() to insn_decode_from_regs() to denote that it
receives regs as param and uses registers from there during decoding.
Free the former name for a more generic version of the function.

No functional changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210304174237.31945-2-bp@alien8.de
2021-03-15 10:53:10 +01:00
Borislav Petkov 0d39131980 Merge 'x86/seves' into x86/core
Pick up dependent changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
2021-03-15 10:49:59 +01:00
Borislav Petkov aa7680f6fe Linux 5.12-rc3
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Merge tag 'v5.12-rc3' into x86/core

Pick up dependent SEV-ES urgent changes to base new work ontop.

Signed-off-by: Borislav Petkov <bp@suse.de>
2021-03-15 10:49:00 +01:00
Linus Torvalds 0a7c10df49 - A couple of SEV-ES fixes and robustifications: verify usermode stack
pointer in NMI is not coming from the syscall gap, correctly track IRQ
 states in the #VC handler and access user insn bytes atomically in same
 handler as latter cannot sleep.
 
 - Balance 32-bit fast syscall exit path to do the proper work on exit
 and thus not confuse audit and ptrace frameworks.
 
 - Two fixes for the ORC unwinder going "off the rails" into KASAN
 redzones and when ORC data is missing.
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Merge tag 'x86_urgent_for_v5.12_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Borislav Petkov:

 - A couple of SEV-ES fixes and robustifications: verify usermode stack
   pointer in NMI is not coming from the syscall gap, correctly track
   IRQ states in the #VC handler and access user insn bytes atomically
   in same handler as latter cannot sleep.

 - Balance 32-bit fast syscall exit path to do the proper work on exit
   and thus not confuse audit and ptrace frameworks.

 - Two fixes for the ORC unwinder going "off the rails" into KASAN
   redzones and when ORC data is missing.

* tag 'x86_urgent_for_v5.12_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/sev-es: Use __copy_from_user_inatomic()
  x86/sev-es: Correctly track IRQ states in runtime #VC handler
  x86/sev-es: Check regs->sp is trusted before adjusting #VC IST stack
  x86/sev-es: Introduce ip_within_syscall_gap() helper
  x86/entry: Fix entry/exit mismatch on failed fast 32-bit syscalls
  x86/unwind/orc: Silence warnings caused by missing ORC data
  x86/unwind/orc: Disable KASAN checking in the ORC unwinder, part 2
2021-03-14 12:48:10 -07:00
Linus Torvalds 9d0c8e793f More fixes for ARM and x86.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Paolo Bonzini:
 "More fixes for ARM and x86"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: LAPIC: Advancing the timer expiration on guest initiated write
  KVM: x86/mmu: Skip !MMU-present SPTEs when removing SP in exclusive mode
  KVM: kvmclock: Fix vCPUs > 64 can't be online/hotpluged
  kvm: x86: annotate RCU pointers
  KVM: arm64: Fix exclusive limit for IPA size
  KVM: arm64: Reject VM creation when the default IPA size is unsupported
  KVM: arm64: Ensure I-cache isolation between vcpus of a same VM
  KVM: arm64: Don't use cbz/adr with external symbols
  KVM: arm64: Fix range alignment when walking page tables
  KVM: arm64: Workaround firmware wrongly advertising GICv2-on-v3 compatibility
  KVM: arm64: Rename __vgic_v3_get_ich_vtr_el2() to __vgic_v3_get_gic_config()
  KVM: arm64: Don't access PMSELR_EL0/PMUSERENR_EL0 when no PMU is available
  KVM: arm64: Turn kvm_arm_support_pmu_v3() into a static key
  KVM: arm64: Fix nVHE hyp panic host context restore
  KVM: arm64: Avoid corrupting vCPU context register in guest exit
  KVM: arm64: nvhe: Save the SPE context early
  kvm: x86: use NULL instead of using plain integer as pointer
  KVM: SVM: Connect 'npt' module param to KVM's internal 'npt_enabled'
  KVM: x86: Ensure deadline timer has truly expired before posting its IRQ
2021-03-14 12:35:02 -07:00
Wanpeng Li d7eb79c629 KVM: kvmclock: Fix vCPUs > 64 can't be online/hotpluged
# lscpu
Architecture:          x86_64
CPU op-mode(s):        32-bit, 64-bit
Byte Order:            Little Endian
CPU(s):                88
On-line CPU(s) list:   0-63
Off-line CPU(s) list:  64-87

# cat /proc/cmdline
BOOT_IMAGE=/vmlinuz-5.10.0-rc3-tlinux2-0050+ root=/dev/mapper/cl-root ro
rd.lvm.lv=cl/root rhgb quiet console=ttyS0 LANG=en_US .UTF-8 no-kvmclock-vsyscall

# echo 1 > /sys/devices/system/cpu/cpu76/online
-bash: echo: write error: Cannot allocate memory

The per-cpu vsyscall pvclock data pointer assigns either an element of the
static array hv_clock_boot (#vCPU <= 64) or dynamically allocated memory
hvclock_mem (vCPU > 64), the dynamically memory will not be allocated if
kvmclock vsyscall is disabled, this can result in cpu hotpluged fails in
kvmclock_setup_percpu() which returns -ENOMEM. It's broken for no-vsyscall
and sometimes you end up with vsyscall disabled if the host does something
strange. This patch fixes it by allocating this dynamically memory
unconditionally even if vsyscall is disabled.

Fixes: 6a1cac56f4 ("x86/kvm: Use __bss_decrypted attribute in shared variables")
Reported-by: Zelin Deng <zelin.deng@linux.alibaba.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: stable@vger.kernel.org#v4.19-rc5+
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Message-Id: <1614130683-24137-1-git-send-email-wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-12 13:18:16 -05:00
Juergen Gross 054ac8ad5e x86/paravirt: Have only one paravirt patch function
There is no need any longer to have different paravirt patch functions
for native and Xen. Eliminate native_patch() and rename
paravirt_patch_default() to paravirt_patch().

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210311142319.4723-15-jgross@suse.com
2021-03-11 20:11:09 +01:00
Juergen Gross fafe5e7422 x86/paravirt: Switch functions with custom code to ALTERNATIVE
Instead of using paravirt patching for custom code sequences use
ALTERNATIVE for the functions with custom code replacements.

Instead of patching an ud2 instruction for unpopulated vector entries
into the caller site, use a simple function just calling BUG() as a
replacement.

Simplify the register defines for assembler paravirt calling, as there
isn't much usage left.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210311142319.4723-14-jgross@suse.com
2021-03-11 20:07:01 +01:00
Juergen Gross ae755b5a45 x86/paravirt: Switch iret pvops to ALTERNATIVE
The iret paravirt op is rather special as it is using a jmp instead
of a call instruction. Switch it to ALTERNATIVE.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210311142319.4723-12-jgross@suse.com
2021-03-11 19:58:54 +01:00
Juergen Gross 33634e42e3 x86/paravirt: Remove no longer needed 32-bit pvops cruft
PVOP_VCALL4() is only used for Xen PV, while PVOP_CALL4() isn't used
at all. Keep PVOP_CALL4() for 64 bits due to symmetry reasons.

This allows to remove the 32-bit definitions of those macros leading
to a substantial simplification of the paravirt macros, as those were
the only ones needing non-empty "pre" and "post" parameters.

PVOP_CALLEE2() and PVOP_VCALLEE2() are used nowhere, so remove them.

Another no longer needed case is special handling of return types
larger than unsigned long. Replace that with a BUILD_BUG_ON().

DISABLE_INTERRUPTS() is used in 32-bit code only, so it can just be
replaced by cli.

INTERRUPT_RETURN in 32-bit code can be replaced by iret.

ENABLE_INTERRUPTS is used nowhere, so it can be removed.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210311142319.4723-10-jgross@suse.com
2021-03-11 19:51:55 +01:00
Juergen Gross 4e6292114c x86/paravirt: Add new features for paravirt patching
For being able to switch paravirt patching from special cased custom
code sequences to ALTERNATIVE handling some X86_FEATURE_* are needed
as new features. This enables to have the standard indirect pv call
as the default code and to patch that with the non-Xen custom code
sequence via ALTERNATIVE patching later.

Make sure paravirt patching is performed before alternatives patching.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210311142319.4723-9-jgross@suse.com
2021-03-11 19:51:49 +01:00
Juergen Gross dda7bb7648 x86/alternative: Support not-feature
Add support for alternative patching for the case a feature is not
present on the current CPU. For users of ALTERNATIVE() and friends, an
inverted feature is specified by applying the ALT_NOT() macro to it,
e.g.:

  ALTERNATIVE(old, new, ALT_NOT(feature));

Committer note:

The decision to encode the NOT-bit in the feature bit itself is because
a future change which would make objtool generate such alternative
calls, would keep the code in objtool itself fairly simple.

Also, this allows for the alternative macros to support the NOT feature
without having to change them.

Finally, the u16 cpuid member encoding the X86_FEATURE_ flags is not an
ABI so if more bits are needed, cpuid itself can be enlarged or a flags
field can be added to struct alt_instr after having considered the size
growth in either cases.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210311142319.4723-6-jgross@suse.com
2021-03-11 16:44:01 +01:00
Juergen Gross a0e2bf7cb7 x86/paravirt: Switch time pvops functions to use static_call()
The time pvops functions are the only ones left which might be
used in 32-bit mode and which return a 64-bit value.

Switch them to use the static_call() mechanism instead of pvops, as
this allows quite some simplification of the pvops implementation.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210311142319.4723-5-jgross@suse.com
2021-03-11 16:17:52 +01:00
Joerg Roedel bffe30dd9f x86/sev-es: Use __copy_from_user_inatomic()
The #VC handler must run in atomic context and cannot sleep. This is a
problem when it tries to fetch instruction bytes from user-space via
copy_from_user().

Introduce a insn_fetch_from_user_inatomic() helper which uses
__copy_from_user_inatomic() to safely copy the instruction bytes to
kernel memory in the #VC handler.

Fixes: 5e3427a7bc ("x86/sev-es: Handle instruction fetches from user-space")
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: stable@vger.kernel.org # v5.10+
Link: https://lkml.kernel.org/r/20210303141716.29223-6-joro@8bytes.org
2021-03-09 12:37:54 +01:00
Joerg Roedel 62441a1fb5 x86/sev-es: Correctly track IRQ states in runtime #VC handler
Call irqentry_nmi_enter()/irqentry_nmi_exit() in the #VC handler to
correctly track the IRQ state during its execution.

Fixes: 0786138c78 ("x86/sev-es: Add a Runtime #VC Exception Handler")
Reported-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: stable@vger.kernel.org # v5.10+
Link: https://lkml.kernel.org/r/20210303141716.29223-5-joro@8bytes.org
2021-03-09 12:33:46 +01:00
Joerg Roedel 545ac14c16 x86/sev-es: Check regs->sp is trusted before adjusting #VC IST stack
The code in the NMI handler to adjust the #VC handler IST stack is
needed in case an NMI hits when the #VC handler is still using its IST
stack.

But the check for this condition also needs to look if the regs->sp
value is trusted, meaning it was not set by user-space. Extend the check
to not use regs->sp when the NMI interrupted user-space code or the
SYSCALL gap.

Fixes: 315562c9af ("x86/sev-es: Adjust #VC IST Stack on entering NMI handler")
Reported-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: stable@vger.kernel.org # 5.10+
Link: https://lkml.kernel.org/r/20210303141716.29223-3-joro@8bytes.org
2021-03-09 12:26:26 +01:00
Joerg Roedel 78a81d88f6 x86/sev-es: Introduce ip_within_syscall_gap() helper
Introduce a helper to check whether an exception came from the syscall
gap and use it in the SEV-ES code. Extend the check to also cover the
compatibility SYSCALL entry path.

Fixes: 315562c9af ("x86/sev-es: Adjust #VC IST Stack on entering NMI handler")
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: stable@vger.kernel.org # 5.10+
Link: https://lkml.kernel.org/r/20210303141716.29223-2-joro@8bytes.org
2021-03-08 14:22:17 +01:00
Andy Lutomirski 3fb0fdb3bb x86/stackprotector/32: Make the canary into a regular percpu variable
On 32-bit kernels, the stackprotector canary is quite nasty -- it is
stored at %gs:(20), which is nasty because 32-bit kernels use %fs for
percpu storage.  It's even nastier because it means that whether %gs
contains userspace state or kernel state while running kernel code
depends on whether stackprotector is enabled (this is
CONFIG_X86_32_LAZY_GS), and this setting radically changes the way
that segment selectors work.  Supporting both variants is a
maintenance and testing mess.

Merely rearranging so that percpu and the stack canary
share the same segment would be messy as the 32-bit percpu address
layout isn't currently compatible with putting a variable at a fixed
offset.

Fortunately, GCC 8.1 added options that allow the stack canary to be
accessed as %fs:__stack_chk_guard, effectively turning it into an ordinary
percpu variable.  This lets us get rid of all of the code to manage the
stack canary GDT descriptor and the CONFIG_X86_32_LAZY_GS mess.

(That name is special.  We could use any symbol we want for the
 %fs-relative mode, but for CONFIG_SMP=n, gcc refuses to let us use any
 name other than __stack_chk_guard.)

Forcibly disable stackprotector on older compilers that don't support
the new options and turn the stack canary into a percpu variable. The
"lazy GS" approach is now used for all 32-bit configurations.

Also makes load_gs_index() work on 32-bit kernels. On 64-bit kernels,
it loads the GS selector and updates the user GSBASE accordingly. (This
is unchanged.) On 32-bit kernels, it loads the GS selector and updates
GSBASE, which is now always the user base. This means that the overall
effect is the same on 32-bit and 64-bit, which avoids some ifdeffery.

 [ bp: Massage commit message. ]

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/c0ff7dba14041c7e5d1cae5d4df052f03759bef3.1613243844.git.luto@kernel.org
2021-03-08 13:19:05 +01:00
Josh Poimboeuf b59cc97674 x86/unwind/orc: Silence warnings caused by missing ORC data
The ORC unwinder attempts to fall back to frame pointers when ORC data
is missing for a given instruction.  It sets state->error, but then
tries to keep going as a best-effort type of thing.  That may result in
further warnings if the unwinder gets lost.

Until we have some way to register generated code with the unwinder,
missing ORC will be expected, and occasionally going off the rails will
also be expected.  So don't warn about it.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Ivan Babrou <ivan@cloudflare.com>
Link: https://lkml.kernel.org/r/06d02c4bbb220bd31668db579278b0352538efbb.1612534649.git.jpoimboe@redhat.com
2021-03-06 13:09:45 +01:00
Josh Poimboeuf e504e74cc3 x86/unwind/orc: Disable KASAN checking in the ORC unwinder, part 2
KASAN reserves "redzone" areas between stack frames in order to detect
stack overruns.  A read or write to such an area triggers a KASAN
"stack-out-of-bounds" BUG.

Normally, the ORC unwinder stays in-bounds and doesn't access the
redzone.  But sometimes it can't find ORC metadata for a given
instruction.  This can happen for code which is missing ORC metadata, or
for generated code.  In such cases, the unwinder attempts to fall back
to frame pointers, as a best-effort type thing.

This fallback often works, but when it doesn't, the unwinder can get
confused and go off into the weeds into the KASAN redzone, triggering
the aforementioned KASAN BUG.

But in this case, the unwinder's confusion is actually harmless and
working as designed.  It already has checks in place to prevent
off-stack accesses, but those checks get short-circuited by the KASAN
BUG.  And a BUG is a lot more disruptive than a harmless unwinder
warning.

Disable the KASAN checks by using READ_ONCE_NOCHECK() for all stack
accesses.  This finishes the job started by commit 881125bfe6
("x86/unwind: Disable KASAN checking in the ORC unwinder"), which only
partially fixed the issue.

Fixes: ee9f8fce99 ("x86/unwind: Add the ORC unwinder")
Reported-by: Ivan Babrou <ivan@cloudflare.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Tested-by: Ivan Babrou <ivan@cloudflare.com>
Cc: stable@kernel.org
Link: https://lkml.kernel.org/r/9583327904ebbbeda399eca9c56d6c7085ac20fe.1612534649.git.jpoimboe@redhat.com
2021-03-06 13:09:37 +01:00
Borislav Petkov f3db3365c0 x86/sev-es: Remove subtraction of res variable
vc_decode_insn() calls copy_from_kernel_nofault() by way of
vc_fetch_insn_kernel() to fetch 15 bytes max of opcodes to decode.

copy_from_kernel_nofault() returns negative on error and 0 on success.
The error case is handled by returning ES_EXCEPTION.

In the success case, the ret variable which contains the return value is
0 so there's no need to subtract it from MAX_INSN_SIZE when initializing
the insn buffer for further decoding. Remove it.

No functional changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Link: https://lkml.kernel.org/r/20210223111130.16201-1-bp@alien8.de
2021-03-06 12:08:53 +01:00
Linus Torvalds 5695e51619 io_uring-worker.v3-2021-02-25
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Merge tag 'io_uring-worker.v3-2021-02-25' of git://git.kernel.dk/linux-block

Pull io_uring thread rewrite from Jens Axboe:
 "This converts the io-wq workers to be forked off the tasks in question
  instead of being kernel threads that assume various bits of the
  original task identity.

  This kills > 400 lines of code from io_uring/io-wq, and it's the worst
  part of the code. We've had several bugs in this area, and the worry
  is always that we could be missing some pieces for file types doing
  unusual things (recent /dev/tty example comes to mind, userfaultfd
  reads installing file descriptors is another fun one... - both of
  which need special handling, and I bet it's not the last weird oddity
  we'll find).

  With these identical workers, we can have full confidence that we're
  never missing anything. That, in itself, is a huge win. Outside of
  that, it's also more efficient since we're not wasting space and code
  on tracking state, or switching between different states.

  I'm sure we're going to find little things to patch up after this
  series, but testing has been pretty thorough, from the usual
  regression suite to production. Any issue that may crop up should be
  manageable.

  There's also a nice series of further reductions we can do on top of
  this, but I wanted to get the meat of it out sooner rather than later.
  The general worry here isn't that it's fundamentally broken. Most of
  the little issues we've found over the last week have been related to
  just changes in how thread startup/exit is done, since that's the main
  difference between using kthreads and these kinds of threads. In fact,
  if all goes according to plan, I want to get this into the 5.10 and
  5.11 stable branches as well.

  That said, the changes outside of io_uring/io-wq are:

   - arch setup, simple one-liner to each arch copy_thread()
     implementation.

   - Removal of net and proc restrictions for io_uring, they are no
     longer needed or useful"

* tag 'io_uring-worker.v3-2021-02-25' of git://git.kernel.dk/linux-block: (30 commits)
  io-wq: remove now unused IO_WQ_BIT_ERROR
  io_uring: fix SQPOLL thread handling over exec
  io-wq: improve manager/worker handling over exec
  io_uring: ensure SQPOLL startup is triggered before error shutdown
  io-wq: make buffered file write hashed work map per-ctx
  io-wq: fix race around io_worker grabbing
  io-wq: fix races around manager/worker creation and task exit
  io_uring: ensure io-wq context is always destroyed for tasks
  arch: ensure parisc/powerpc handle PF_IO_WORKER in copy_thread()
  io_uring: cleanup ->user usage
  io-wq: remove nr_process accounting
  io_uring: flag new native workers with IORING_FEAT_NATIVE_WORKERS
  net: remove cmsg restriction from io_uring based send/recvmsg calls
  Revert "proc: don't allow async path resolution of /proc/self components"
  Revert "proc: don't allow async path resolution of /proc/thread-self components"
  io_uring: move SQPOLL thread io-wq forked worker
  io-wq: make io_wq_fork_thread() available to other users
  io-wq: only remove worker from free_list, if it was there
  io_uring: remove io_identity
  io_uring: remove any grabbing of context
  ...
2021-02-27 08:29:02 -08:00
Linus Torvalds 29c395c77a Rework of the X86 irq stack handling:
The irq stack switching was moved out of the ASM entry code in course of
   the entry code consolidation. It ended up being suboptimal in various
   ways.
 
   - Make the stack switching inline so the stackpointer manipulation is not
     longer at an easy to find place.
 
   - Get rid of the unnecessary indirect call.
 
   - Avoid the double stack switching in interrupt return and reuse the
     interrupt stack for softirq handling.
 
   - A objtool fix for CONFIG_FRAME_POINTER=y builds where it got confused
     about the stack pointer manipulation.
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Merge tag 'x86-entry-2021-02-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 irq entry updates from Thomas Gleixner:
 "The irq stack switching was moved out of the ASM entry code in course
  of the entry code consolidation. It ended up being suboptimal in
  various ways.

  This reworks the X86 irq stack handling:

   - Make the stack switching inline so the stackpointer manipulation is
     not longer at an easy to find place.

   - Get rid of the unnecessary indirect call.

   - Avoid the double stack switching in interrupt return and reuse the
     interrupt stack for softirq handling.

   - A objtool fix for CONFIG_FRAME_POINTER=y builds where it got
     confused about the stack pointer manipulation"

* tag 'x86-entry-2021-02-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool: Fix stack-swizzle for FRAME_POINTER=y
  um: Enforce the usage of asm-generic/softirq_stack.h
  x86/softirq/64: Inline do_softirq_own_stack()
  softirq: Move do_softirq_own_stack() to generic asm header
  softirq: Move __ARCH_HAS_DO_SOFTIRQ to Kconfig
  x86: Select CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK
  x86/softirq: Remove indirection in do_softirq_own_stack()
  x86/entry: Use run_sysvec_on_irqstack_cond() for XEN upcall
  x86/entry: Convert device interrupts to inline stack switching
  x86/entry: Convert system vectors to irq stack macro
  x86/irq: Provide macro for inlining irq stack switching
  x86/apic: Split out spurious handling code
  x86/irq/64: Adjust the per CPU irq stack pointer by 8
  x86/irq: Sanitize irq stack tracking
  x86/entry: Fix instrumentation annotation
2021-02-24 16:32:23 -08:00
Linus Torvalds c4fbde84fe Simple Firmware Interface (SFI) support removal for v5.12-rc1
Drop support for depercated platforms using SFI, drop the entire
 support for SFI that has been long deprecated too and make some
 janitorial changes on top of that (Andy Shevchenko).
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Merge tag 'sfi-removal-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull Simple Firmware Interface (SFI) support removal from Rafael Wysocki:
 "Drop support for depercated platforms using SFI, drop the entire
  support for SFI that has been long deprecated too and make some
  janitorial changes on top of that (Andy Shevchenko)"

* tag 'sfi-removal-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  x86/platform/intel-mid: Update Copyright year and drop file names
  x86/platform/intel-mid: Remove unused header inclusion in intel-mid.h
  x86/platform/intel-mid: Drop unused __intel_mid_cpu_chip and Co.
  x86/platform/intel-mid: Get rid of intel_scu_ipc_legacy.h
  x86/PCI: Describe @reg for type1_access_ok()
  x86/PCI: Get rid of custom x86 model comparison
  sfi: Remove framework for deprecated firmware
  cpufreq: sfi-cpufreq: Remove driver for deprecated firmware
  media: atomisp: Remove unused header
  mfd: intel_msic: Remove driver for deprecated platform
  x86/apb_timer: Remove driver for deprecated platform
  x86/platform/intel-mid: Remove unused leftovers (vRTC)
  x86/platform/intel-mid: Remove unused leftovers (msic)
  x86/platform/intel-mid: Remove unused leftovers (msic_thermal)
  x86/platform/intel-mid: Remove unused leftovers (msic_power_btn)
  x86/platform/intel-mid: Remove unused leftovers (msic_gpio)
  x86/platform/intel-mid: Remove unused leftovers (msic_battery)
  x86/platform/intel-mid: Remove unused leftovers (msic_ocd)
  x86/platform/intel-mid: Remove unused leftovers (msic_audio)
  platform/x86: intel_scu_wdt: Drop mistakenly added const
2021-02-24 10:35:29 -08:00
Linus Torvalds e229b429bb Char/Misc driver patches for 5.12-rc1
Here is the large set of char/misc/whatever driver subsystem updates for
 5.12-rc1.  Over time it seems like this tree is collecting more and more
 tiny driver subsystems in one place, making it easier for those
 maintainers, which is why this is getting larger.
 
 Included in here are:
 	- coresight driver updates
 	- habannalabs driver updates
 	- virtual acrn driver addition (proper acks from the x86
 	  maintainers)
 	- broadcom misc driver addition
 	- speakup driver updates
 	- soundwire driver updates
 	- fpga driver updates
 	- amba driver updates
 	- mei driver updates
 	- vfio driver updates
 	- greybus driver updates
 	- nvmeem driver updates
 	- phy driver updates
 	- mhi driver updates
 	- interconnect driver udpates
 	- fsl-mc bus driver updates
 	- random driver fix
 	- some small misc driver updates (rtsx, pvpanic, etc.)
 
 All of these have been in linux-next for a while, with the only reported
 issue being a merge conflict in include/linux/mod_devicetable.h that you
 will hit in your tree due to the dfl_device_id addition from the fpga
 subsystem in here.  The resolution should be simple.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the large set of char/misc/whatever driver subsystem updates
  for 5.12-rc1. Over time it seems like this tree is collecting more and
  more tiny driver subsystems in one place, making it easier for those
  maintainers, which is why this is getting larger.

  Included in here are:

   - coresight driver updates

   - habannalabs driver updates

   - virtual acrn driver addition (proper acks from the x86 maintainers)

   - broadcom misc driver addition

   - speakup driver updates

   - soundwire driver updates

   - fpga driver updates

   - amba driver updates

   - mei driver updates

   - vfio driver updates

   - greybus driver updates

   - nvmeem driver updates

   - phy driver updates

   - mhi driver updates

   - interconnect driver udpates

   - fsl-mc bus driver updates

   - random driver fix

   - some small misc driver updates (rtsx, pvpanic, etc.)

  All of these have been in linux-next for a while, with the only
  reported issue being a merge conflict due to the dfl_device_id
  addition from the fpga subsystem in here"

* tag 'char-misc-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (311 commits)
  spmi: spmi-pmic-arb: Fix hw_irq overflow
  Documentation: coresight: Add PID tracing description
  coresight: etm-perf: Support PID tracing for kernel at EL2
  coresight: etm-perf: Clarify comment on perf options
  ACRN: update MAINTAINERS: mailing list is subscribers-only
  regmap: sdw-mbq: use MODULE_LICENSE("GPL")
  regmap: sdw: use no_pm routines for SoundWire 1.2 MBQ
  regmap: sdw: use _no_pm functions in regmap_read/write
  soundwire: intel: fix possible crash when no device is detected
  MAINTAINERS: replace my with email with replacements
  mhi: Fix double dma free
  uapi: map_to_7segment: Update example in documentation
  uio: uio_pci_generic: don't fail probe if pdev->irq equals to IRQ_NOTCONNECTED
  drivers/misc/vmw_vmci: restrict too big queue size in qp_host_alloc_queue
  firewire: replace tricky statement by two simple ones
  vme: make remove callback return void
  firmware: google: make coreboot driver's remove callback return void
  firmware: xilinx: Use explicit values for all enum values
  sample/acrn: Introduce a sample of HSM ioctl interface usage
  virt: acrn: Introduce an interface for Service VM to control vCPU
  ...
2021-02-24 10:25:37 -08:00
Linus Torvalds a56ff24efb objtool updates:
- Make objtool work for big-endian cross compiles
 
  - Make stack tracking via stack pointer memory operations match push/pop
    semantics to prepare for architectures w/o PUSH/POP instructions.
 
  - Add support for analyzing alternatives
 
  - Improve retpoline detection and handling
 
  - Improve assembly code coverage on x86
 
  - Provide support for inlined stack switching
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Merge tag 'objtool-core-2021-02-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull objtool updates from Thomas Gleixner:

 - Make objtool work for big-endian cross compiles

 - Make stack tracking via stack pointer memory operations match
   push/pop semantics to prepare for architectures w/o PUSH/POP
   instructions.

 - Add support for analyzing alternatives

 - Improve retpoline detection and handling

 - Improve assembly code coverage on x86

 - Provide support for inlined stack switching

* tag 'objtool-core-2021-02-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
  objtool: Support stack-swizzle
  objtool,x86: Additionally decode: mov %rsp, (%reg)
  x86/unwind/orc: Change REG_SP_INDIRECT
  x86/power: Support objtool validation in hibernate_asm_64.S
  x86/power: Move restore_registers() to top of the file
  x86/power: Annotate indirect branches as safe
  x86/acpi: Support objtool validation in wakeup_64.S
  x86/acpi: Annotate indirect branch as safe
  x86/ftrace: Support objtool vmlinux.o validation in ftrace_64.S
  x86/xen/pvh: Annotate indirect branch as safe
  x86/xen: Support objtool vmlinux.o validation in xen-head.S
  x86/xen: Support objtool validation in xen-asm.S
  objtool: Add xen_start_kernel() to noreturn list
  objtool: Combine UNWIND_HINT_RET_OFFSET and UNWIND_HINT_FUNC
  objtool: Add asm version of STACK_FRAME_NON_STANDARD
  objtool: Assume only ELF functions do sibling calls
  x86/ftrace: Add UNWIND_HINT_FUNC annotation for ftrace_stub
  objtool: Support retpoline jump detection for vmlinux.o
  objtool: Fix ".cold" section suffix check for newer versions of GCC
  objtool: Fix retpoline detection in asm code
  ...
2021-02-23 09:56:13 -08:00