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Commit 986b37c0 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull x86 cleanups and msr updates from Ingo Molnar:
 "The main change is a performance/latency improvement to /dev/msr
  access. The rest are misc cleanups"

* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/msr: Make rdmsrl_safe_on_cpu() scheduling safe as well
  x86/cpuid: Allow cpuid_read() to schedule
  x86/msr: Allow rdmsr_safe_on_cpu() to schedule
  x86/rtc: Stop using deprecated functions
  x86/dumpstack: Unify show_regs()
  x86/fault: Do not print IP in show_fault_oops()
  x86/MSR: Move native_* variants to msr.h
parents e68b4bad 9b9a5135

arch/x86/include/asm/microcode.h

+0 −14
Original line number Diff line number Diff line
@@ -6,20 +6,6 @@ 
#include <linux/earlycpio.h>

#include <linux/initrd.h>



#define native_rdmsr(msr, val1, val2)			\

do {							\

	u64 __val = __rdmsr((msr));			\

	(void)((val1) = (u32)__val);			\

	(void)((val2) = (u32)(__val >> 32));		\

} while (0)



#define native_wrmsr(msr, low, high)			\

	__wrmsr(msr, low, high)



#define native_wrmsrl(msr, val)				\

	__wrmsr((msr), (u32)((u64)(val)),		\

		       (u32)((u64)(val) >> 32))



struct ucode_patch {

	struct list_head plist;

	void *data;		/* Intel uses only this one */

arch/x86/include/asm/msr.h

+14 −0
Original line number Diff line number Diff line
@@ -108,6 +108,20 @@ static inline void notrace __wrmsr(unsigned int msr, u32 low, u32 high) 
		     : : "c" (msr), "a"(low), "d" (high) : "memory");

}



#define native_rdmsr(msr, val1, val2)			\

do {							\

	u64 __val = __rdmsr((msr));			\

	(void)((val1) = (u32)__val);			\

	(void)((val2) = (u32)(__val >> 32));		\

} while (0)



#define native_wrmsr(msr, low, high)			\

	__wrmsr(msr, low, high)



#define native_wrmsrl(msr, val)				\

	__wrmsr((msr), (u32)((u64)(val)),		\

		       (u32)((u64)(val) >> 32))



static inline unsigned long long native_read_msr(unsigned int msr)

{

	unsigned long long val;

arch/x86/include/asm/stacktrace.h

+0 −2
Original line number Diff line number Diff line
@@ -87,8 +87,6 @@ get_stack_pointer(struct task_struct *task, struct pt_regs *regs) 
void show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs,

			unsigned long *stack, char *log_lvl);



extern unsigned int code_bytes;



/* The form of the top of the frame on the stack */

struct stack_frame {

	struct stack_frame *next_frame;

arch/x86/kernel/cpuid.c

+26 −8
Original line number Diff line number Diff line
@@ -40,6 +40,7 @@ 
#include <linux/notifier.h>

#include <linux/uaccess.h>

#include <linux/gfp.h>

#include <linux/completion.h>



#include <asm/processor.h>

#include <asm/msr.h>
@@ -47,19 +48,27 @@ 
static struct class *cpuid_class;

static enum cpuhp_state cpuhp_cpuid_state;



struct cpuid_regs_done {

	struct cpuid_regs regs;

	struct completion done;

};



static void cpuid_smp_cpuid(void *cmd_block)

{

	struct cpuid_regs *cmd = (struct cpuid_regs *)cmd_block;

	struct cpuid_regs_done *cmd = cmd_block;



	cpuid_count(cmd->regs.eax, cmd->regs.ecx,

		    &cmd->regs.eax, &cmd->regs.ebx,

		    &cmd->regs.ecx, &cmd->regs.edx);



	cpuid_count(cmd->eax, cmd->ecx,

		    &cmd->eax, &cmd->ebx, &cmd->ecx, &cmd->edx);

	complete(&cmd->done);

}



static ssize_t cpuid_read(struct file *file, char __user *buf,

			  size_t count, loff_t *ppos)

{

	char __user *tmp = buf;

	struct cpuid_regs cmd;

	struct cpuid_regs_done cmd;

	int cpu = iminor(file_inode(file));

	u64 pos = *ppos;

	ssize_t bytes = 0;
@@ -68,19 +77,28 @@ static ssize_t cpuid_read(struct file *file, char __user *buf, 
	if (count % 16)

		return -EINVAL;	/* Invalid chunk size */



	init_completion(&cmd.done);

	for (; count; count -= 16) {

		cmd.eax = pos;

		cmd.ecx = pos >> 32;

		err = smp_call_function_single(cpu, cpuid_smp_cpuid, &cmd, 1);

		call_single_data_t csd = {

			.func = cpuid_smp_cpuid,

			.info = &cmd,

		};



		cmd.regs.eax = pos;

		cmd.regs.ecx = pos >> 32;



		err = smp_call_function_single_async(cpu, &csd);

		if (err)

			break;

		if (copy_to_user(tmp, &cmd, 16)) {

		wait_for_completion(&cmd.done);

		if (copy_to_user(tmp, &cmd.regs, 16)) {

			err = -EFAULT;

			break;

		}

		tmp += 16;

		bytes += 16;

		*ppos = ++pos;

		reinit_completion(&cmd.done);

	}



	return bytes ? bytes : err;

arch/x86/kernel/dumpstack.c

+48 −1
Original line number Diff line number Diff line
@@ -24,7 +24,7 @@ 


int panic_on_unrecovered_nmi;

int panic_on_io_nmi;

unsigned int code_bytes = 64;

static unsigned int code_bytes = 64;

static int die_counter;



bool in_task_stack(unsigned long *stack, struct task_struct *task,
@@ -375,3 +375,50 @@ static int __init code_bytes_setup(char *s) 
	return 1;

}

__setup("code_bytes=", code_bytes_setup);



void show_regs(struct pt_regs *regs)

{

	bool all = true;

	int i;



	show_regs_print_info(KERN_DEFAULT);



	if (IS_ENABLED(CONFIG_X86_32))

		all = !user_mode(regs);



	__show_regs(regs, all);



	/*

	 * When in-kernel, we also print out the stack and code at the

	 * time of the fault..

	 */

	if (!user_mode(regs)) {

		unsigned int code_prologue = code_bytes * 43 / 64;

		unsigned int code_len = code_bytes;

		unsigned char c;

		u8 *ip;



		show_trace_log_lvl(current, regs, NULL, KERN_DEFAULT);



		printk(KERN_DEFAULT "Code: ");



		ip = (u8 *)regs->ip - code_prologue;

		if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) {

			/* try starting at IP */

			ip = (u8 *)regs->ip;

			code_len = code_len - code_prologue + 1;

		}

		for (i = 0; i < code_len; i++, ip++) {

			if (ip < (u8 *)PAGE_OFFSET ||

					probe_kernel_address(ip, c)) {

				pr_cont(" Bad RIP value.");

				break;

			}

			if (ip == (u8 *)regs->ip)

				pr_cont("<%02x> ", c);

			else

				pr_cont("%02x ", c);

		}

	}

	pr_cont("\n");

}