[PATCH 5.15 114/567] x86/microcode: Rip out the OLD_INTERFACE

From: Borislav Petkov bp@suse.de

[ Upstream commit 181b6f40e9ea80c76756d4d0cdeed396016c487e ]

Everything should be using the early initrd loading by now.

Signed-off-by: Borislav Petkov bp@suse.de Signed-off-by: Thomas Gleixner tglx@linutronix.de Link: https://lore.kernel.org/r/20220525161232.14924-2-bp@alien8.de Stable-dep-of: c0dd9245aa9e ("x86/microcode: Check CPU capabilities after late microcode update correctly") Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/Kconfig | 12 ---- arch/x86/kernel/cpu/microcode/core.c | 100 --------------------------- 2 files changed, 112 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 0f2234cd8453c..da87b3bfc9132 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1320,18 +1320,6 @@ config MICROCODE_AMD If you select this option, microcode patch loading support for AMD processors will be enabled.

-config MICROCODE_OLD_INTERFACE - bool "Ancient loading interface (DEPRECATED)" - default n - depends on MICROCODE - help - DO NOT USE THIS! This is the ancient /dev/cpu/microcode interface - which was used by userspace tools like iucode_tool and microcode.ctl. - It is inadequate because it runs too late to be able to properly - load microcode on a machine and it needs special tools. Instead, you - should've switched to the early loading method with the initrd or - builtin microcode by now: Documentation/x86/microcode.rst - config X86_MSR tristate "/dev/cpu/*/msr - Model-specific register support" help diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c index 150ebfb8c12ed..951677121c77d 100644 --- a/arch/x86/kernel/cpu/microcode/core.c +++ b/arch/x86/kernel/cpu/microcode/core.c @@ -390,98 +390,6 @@ static int apply_microcode_on_target(int cpu) return ret; }

-#ifdef CONFIG_MICROCODE_OLD_INTERFACE -static int do_microcode_update(const void __user *buf, size_t size) -{ - int error = 0; - int cpu; - - for_each_online_cpu(cpu) { - struct ucode_cpu_info *uci = ucode_cpu_info + cpu; - enum ucode_state ustate; - - if (!uci->valid) - continue; - - ustate = microcode_ops->request_microcode_user(cpu, buf, size); - if (ustate == UCODE_ERROR) { - error = -1; - break; - } else if (ustate == UCODE_NEW) { - apply_microcode_on_target(cpu); - } - } - - return error; -} - -static int microcode_open(struct inode *inode, struct file *file) -{ - return capable(CAP_SYS_RAWIO) ? stream_open(inode, file) : -EPERM; -} - -static ssize_t microcode_write(struct file *file, const char __user *buf, - size_t len, loff_t *ppos) -{ - ssize_t ret = -EINVAL; - unsigned long nr_pages = totalram_pages(); - - if ((len >> PAGE_SHIFT) > nr_pages) { - pr_err("too much data (max %ld pages)\n", nr_pages); - return ret; - } - - cpus_read_lock(); - mutex_lock(&microcode_mutex); - - if (do_microcode_update(buf, len) == 0) - ret = (ssize_t)len; - - if (ret > 0) - perf_check_microcode(); - - mutex_unlock(&microcode_mutex); - cpus_read_unlock(); - - return ret; -} - -static const struct file_operations microcode_fops = { - .owner = THIS_MODULE, - .write = microcode_write, - .open = microcode_open, - .llseek = no_llseek, -}; - -static struct miscdevice microcode_dev = { - .minor = MICROCODE_MINOR, - .name = "microcode", - .nodename = "cpu/microcode", - .fops = &microcode_fops, -}; - -static int __init microcode_dev_init(void) -{ - int error; - - error = misc_register(&microcode_dev); - if (error) { - pr_err("can't misc_register on minor=%d\n", MICROCODE_MINOR); - return error; - } - - return 0; -} - -static void __exit microcode_dev_exit(void) -{ - misc_deregister(&microcode_dev); -} -#else -#define microcode_dev_init() 0 -#define microcode_dev_exit() do { } while (0) -#endif - /* fake device for request_firmware */ static struct platform_device *microcode_pdev;

@@ -873,10 +781,6 @@ static int __init microcode_init(void) goto out_driver; }

- error = microcode_dev_init(); - if (error) - goto out_ucode_group; - register_syscore_ops(&mc_syscore_ops); cpuhp_setup_state_nocalls(CPUHP_AP_MICROCODE_LOADER, "x86/microcode:starting", mc_cpu_starting, NULL); @@ -887,10 +791,6 @@ static int __init microcode_init(void)

return 0;

- out_ucode_group: - sysfs_remove_group(&cpu_subsys.dev_root->kobj, - &cpu_root_microcode_group); - out_driver: cpus_read_lock(); mutex_lock(&microcode_mutex);