Re: [PATCH RESEND v2 1/3] x86/cpu: Create helper to parse clearcpuid param
From: Borislav Petkov <bp@alien8.de>
Date: 2025-02-17 11:00:08
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On Wed, Jan 29, 2025 at 03:35:39PM +0000, Brendan Jackman wrote:
+/* + * We parse cpu parameters early because fpu__init_system() is executed
While at it: s/We parse cpu parameters/Parse CPU parameters/
+ * before parse_early_param().
+ */
+static void __init cpu_parse_early_param(void)
+{
+ char arg[128];
+ int arglen;
+
+#ifdef CONFIG_X86_32
+ if (cmdline_find_option_bool(boot_command_line, "no387"))
+#ifdef CONFIG_MATH_EMULATION
+ setup_clear_cpu_cap(X86_FEATURE_FPU);
+#else
+ pr_err("Option 'no387' required CONFIG_MATH_EMULATION enabled.\n");
+#endif
+
+ if (cmdline_find_option_bool(boot_command_line, "nofxsr"))
+ setup_clear_cpu_cap(X86_FEATURE_FXSR);
+#endif
+
+ if (cmdline_find_option_bool(boot_command_line, "noxsave"))
+ setup_clear_cpu_cap(X86_FEATURE_XSAVE);
+
+ if (cmdline_find_option_bool(boot_command_line, "noxsaveopt"))
+ setup_clear_cpu_cap(X86_FEATURE_XSAVEOPT);
+
+ if (cmdline_find_option_bool(boot_command_line, "noxsaves"))
+ setup_clear_cpu_cap(X86_FEATURE_XSAVES);
+
+ if (cmdline_find_option_bool(boot_command_line, "nousershstk"))
+ setup_clear_cpu_cap(X86_FEATURE_USER_SHSTK);
+
+ /* Minimize the gap between FRED is available and available but disabled. */
+ arglen = cmdline_find_option(boot_command_line, "fred", arg, sizeof(arg));
+ if (arglen != 2 || strncmp(arg, "on", 2))
+ setup_clear_cpu_cap(X86_FEATURE_FRED);
+
+ arglen = cmdline_find_option(boot_command_line, "clearcpuid", arg, sizeof(arg));
+ if (arglen <= 0)
+ return;Newline here.
+ parse_clearcpuid(arg); } /* -- 2.48.1.262.g85cc9f2d1e-goog
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette