Merge tag 'objtool-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull objtool updates from Ingo Molnar:

 - klp-build livepatch module generation (Josh Poimboeuf)

   Introduce new objtool features and a klp-build script to generate
   livepatch modules using a source .patch as input.

   This builds on concepts from the longstanding out-of-tree kpatch
   project which began in 2012 and has been used for many years to
   generate livepatch modules for production kernels. However, this is a
   complete rewrite which incorporates hard-earned lessons from 12+
   years of maintaining kpatch.

   Key improvements compared to kpatch-build:

    - Integrated with objtool: Leverages objtool's existing control-flow
      graph analysis to help detect changed functions.

    - Works on vmlinux.o: Supports late-linked objects, making it
      compatible with LTO, IBT, and similar.

    - Simplified code base: ~3k fewer lines of code.

    - Upstream: No more out-of-tree #ifdef hacks, far less cruft.

    - Cleaner internals: Vastly simplified logic for
      symbol/section/reloc inclusion and special section extraction.

    - Robust __LINE__ macro handling: Avoids false positive binary diffs
      caused by the __LINE__ macro by introducing a fix-patch-lines
      script which injects #line directives into the source .patch to
      preserve the original line numbers at compile time.

 - Disassemble code with libopcodes instead of running objdump
   (Alexandre Chartre)

 - Disassemble support (-d option to objtool) by Alexandre Chartre,
   which supports the decoding of various Linux kernel code generation
   specials such as alternatives:

      17ef:  sched_balance_find_dst_group+0x62f                 mov    0x34(%r9),%edx
      17f3:  sched_balance_find_dst_group+0x633               | <alternative.17f3>             | X86_FEATURE_POPCNT
      17f3:  sched_balance_find_dst_group+0x633               | call   0x17f8 <__sw_hweight64> | popcnt %rdi,%rax
      17f8:  sched_balance_find_dst_group+0x638                 cmp    %eax,%edx

   ... jump table alternatives:

      1895:  sched_use_asym_prio+0x5                            test   $0x8,%ch
      1898:  sched_use_asym_prio+0x8                            je     0x18a9 <sched_use_asym_prio+0x19>
      189a:  sched_use_asym_prio+0xa                          | <jump_table.189a>                        | JUMP
      189a:  sched_use_asym_prio+0xa                          | jmp    0x18ae <sched_use_asym_prio+0x1e> | nop2
      189c:  sched_use_asym_prio+0xc                            mov    $0x1,%eax
      18a1:  sched_use_asym_prio+0x11                           and    $0x80,%ecx

   ... exception table alternatives:

    native_read_msr:
      5b80:  native_read_msr+0x0                                                     mov    %edi,%ecx
      5b82:  native_read_msr+0x2                                                   | <ex_table.5b82> | EXCEPTION
      5b82:  native_read_msr+0x2                                                   | rdmsr           | resume at 0x5b84 <native_read_msr+0x4>
      5b84:  native_read_msr+0x4                                                     shl    $0x20,%rdx

   .... x86 feature flag decoding (also see the X86_FEATURE_POPCNT
        example in sched_balance_find_dst_group() above):

      2faaf:  start_thread_common.constprop.0+0x1f                                    jne    0x2fba4 <start_thread_common.constprop.0+0x114>
      2fab5:  start_thread_common.constprop.0+0x25                                  | <alternative.2fab5>                  | X86_FEATURE_ALWAYS                                  | X86_BUG_NULL_SEG
      2fab5:  start_thread_common.constprop.0+0x25                                  | jmp    0x2faba <.altinstr_aux+0x2f4> | jmp    0x4b0 <start_thread_common.constprop.0+0x3f> | nop5
      2faba:  start_thread_common.constprop.0+0x2a                                    mov    $0x2b,%eax

   ... NOP sequence shortening:

      1048e2:  snapshot_write_finalize+0xc2                                            je     0x104917 <snapshot_write_finalize+0xf7>
      1048e4:  snapshot_write_finalize+0xc4                                            nop6
      1048ea:  snapshot_write_finalize+0xca                                            nop11
      1048f5:  snapshot_write_finalize+0xd5                                            nop11
      104900:  snapshot_write_finalize+0xe0                                            mov    %rax,%rcx
      104903:  snapshot_write_finalize+0xe3                                            mov    0x10(%rdx),%rax

   ... and much more.

 - Function validation tracing support (Alexandre Chartre)

 - Various -ffunction-sections fixes (Josh Poimboeuf)

 - Clang AutoFDO (Automated Feedback-Directed Optimizations) support
   (Josh Poimboeuf)

 - Misc fixes and cleanups (Borislav Petkov, Chen Ni, Dylan Hatch, Ingo
   Molnar, John Wang, Josh Poimboeuf, Pankaj Raghav, Peter Zijlstra,
   Thorsten Blum)

* tag 'objtool-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (129 commits)
  objtool: Fix segfault on unknown alternatives
  objtool: Build with disassembly can fail when including bdf.h
  objtool: Trim trailing NOPs in alternative
  objtool: Add wide output for disassembly
  objtool: Compact output for alternatives with one instruction
  objtool: Improve naming of group alternatives
  objtool: Add Function to get the name of a CPU feature
  objtool: Provide access to feature and flags of group alternatives
  objtool: Fix address references in alternatives
  objtool: Disassemble jump table alternatives
  objtool: Disassemble exception table alternatives
  objtool: Print addresses with alternative instructions
  objtool: Disassemble group alternatives
  objtool: Print headers for alternatives
  objtool: Preserve alternatives order
  objtool: Add the --disas=<function-pattern> action
  objtool: Do not validate IBT for .return_sites and .call_sites
  objtool: Improve tracing of alternative instructions
  objtool: Add functions to better name alternatives
  objtool: Identify the different types of alternatives
  ...

1 files changed, 10 insertions, 10 deletions

diff --git a/drivers/tty/synclink_gt.c b/drivers/tty/synclink_gt.c
index 3865b10d2d43..9d591fb291fd 100644
--- a/drivers/tty/synclink_gt.c
+++ b/drivers/tty/synclink_gt.c
@@ -407,9 +407,9 @@ static void  wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value);
 
 static void  msc_set_vcr(struct slgt_info *info);
 
-static int  startup(struct slgt_info *info);
+static int  startup_hw(struct slgt_info *info);
 static int  block_til_ready(struct tty_struct *tty, struct file * filp,struct slgt_info *info);
-static void shutdown(struct slgt_info *info);
+static void shutdown_hw(struct slgt_info *info);
 static void program_hw(struct slgt_info *info);
 static void change_params(struct slgt_info *info);
 
@@ -622,7 +622,7 @@ static int open(struct tty_struct *tty, struct file *filp)
 
 	if (info->port.count == 1) {
 		/* 1st open on this device, init hardware */
-		retval = startup(info);
+		retval = startup_hw(info);
 		if (retval < 0) {
 			mutex_unlock(&info->port.mutex);
 			goto cleanup;
@@ -666,7 +666,7 @@ static void close(struct tty_struct *tty, struct file *filp)
 	flush_buffer(tty);
 	tty_ldisc_flush(tty);
 
-	shutdown(info);
+	shutdown_hw(info);
 	mutex_unlock(&info->port.mutex);
 
 	tty_port_close_end(&info->port, tty);
@@ -687,7 +687,7 @@ static void hangup(struct tty_struct *tty)
 	flush_buffer(tty);
 
 	mutex_lock(&info->port.mutex);
-	shutdown(info);
+	shutdown_hw(info);
 
 	spin_lock_irqsave(&info->port.lock, flags);
 	info->port.count = 0;
@@ -1445,7 +1445,7 @@ static int hdlcdev_open(struct net_device *dev)
 	spin_unlock_irqrestore(&info->netlock, flags);
 
 	/* claim resources and init adapter */
-	if ((rc = startup(info)) != 0) {
+	if ((rc = startup_hw(info)) != 0) {
 		spin_lock_irqsave(&info->netlock, flags);
 		info->netcount=0;
 		spin_unlock_irqrestore(&info->netlock, flags);
@@ -1455,7 +1455,7 @@ static int hdlcdev_open(struct net_device *dev)
 	/* generic HDLC layer open processing */
 	rc = hdlc_open(dev);
 	if (rc) {
-		shutdown(info);
+		shutdown_hw(info);
 		spin_lock_irqsave(&info->netlock, flags);
 		info->netcount = 0;
 		spin_unlock_irqrestore(&info->netlock, flags);
@@ -1499,7 +1499,7 @@ static int hdlcdev_close(struct net_device *dev)
 	netif_stop_queue(dev);
 
 	/* shutdown adapter and release resources */
-	shutdown(info);
+	shutdown_hw(info);
 
 	hdlc_close(dev);
 
@@ -2328,7 +2328,7 @@ static irqreturn_t slgt_interrupt(int dummy, void *dev_id)
 	return IRQ_HANDLED;
 }
 
-static int startup(struct slgt_info *info)
+static int startup_hw(struct slgt_info *info)
 {
 	DBGINFO(("%s startup\n", info->device_name));
 
@@ -2361,7 +2361,7 @@ static int startup(struct slgt_info *info)
 /*
  *  called by close() and hangup() to shutdown hardware
  */
-static void shutdown(struct slgt_info *info)
+static void shutdown_hw(struct slgt_info *info)
 {
 	unsigned long flags;