sys: Remove BKL from sys_reboot
Serialization of sys_reboot can be done local. The BKL is not protecting anything else. LKML-Reference: <20091010153349.405590702@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
parent
1a6deaea35
commit
6f15fa5008
14
kernel/sys.c
14
kernel/sys.c
@ -8,7 +8,6 @@
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#include <linux/mm.h>
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#include <linux/mm.h>
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#include <linux/utsname.h>
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#include <linux/utsname.h>
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#include <linux/mman.h>
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#include <linux/mman.h>
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#include <linux/smp_lock.h>
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#include <linux/notifier.h>
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#include <linux/notifier.h>
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#include <linux/reboot.h>
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#include <linux/reboot.h>
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#include <linux/prctl.h>
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#include <linux/prctl.h>
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@ -349,6 +348,9 @@ void kernel_power_off(void)
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machine_power_off();
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machine_power_off();
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}
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}
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EXPORT_SYMBOL_GPL(kernel_power_off);
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EXPORT_SYMBOL_GPL(kernel_power_off);
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static DEFINE_MUTEX(reboot_mutex);
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/*
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/*
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* Reboot system call: for obvious reasons only root may call it,
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* Reboot system call: for obvious reasons only root may call it,
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* and even root needs to set up some magic numbers in the registers
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* and even root needs to set up some magic numbers in the registers
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@ -381,7 +383,7 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd,
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if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off)
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if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off)
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cmd = LINUX_REBOOT_CMD_HALT;
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cmd = LINUX_REBOOT_CMD_HALT;
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lock_kernel();
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mutex_lock(&reboot_mutex);
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switch (cmd) {
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switch (cmd) {
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case LINUX_REBOOT_CMD_RESTART:
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case LINUX_REBOOT_CMD_RESTART:
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kernel_restart(NULL);
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kernel_restart(NULL);
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@ -397,20 +399,18 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd,
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case LINUX_REBOOT_CMD_HALT:
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case LINUX_REBOOT_CMD_HALT:
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kernel_halt();
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kernel_halt();
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unlock_kernel();
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do_exit(0);
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do_exit(0);
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panic("cannot halt");
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panic("cannot halt");
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case LINUX_REBOOT_CMD_POWER_OFF:
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case LINUX_REBOOT_CMD_POWER_OFF:
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kernel_power_off();
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kernel_power_off();
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unlock_kernel();
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do_exit(0);
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do_exit(0);
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break;
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break;
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case LINUX_REBOOT_CMD_RESTART2:
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case LINUX_REBOOT_CMD_RESTART2:
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if (strncpy_from_user(&buffer[0], arg, sizeof(buffer) - 1) < 0) {
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if (strncpy_from_user(&buffer[0], arg, sizeof(buffer) - 1) < 0) {
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unlock_kernel();
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ret = -EFAULT;
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return -EFAULT;
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break;
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}
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}
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buffer[sizeof(buffer) - 1] = '\0';
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buffer[sizeof(buffer) - 1] = '\0';
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@ -433,7 +433,7 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd,
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ret = -EINVAL;
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ret = -EINVAL;
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break;
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break;
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}
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}
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unlock_kernel();
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mutex_unlock(&reboot_mutex);
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return ret;
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return ret;
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}
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}
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