| Message ID | 20231205105030.8698-9-xin3.li@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | x86: enable FRED for x86-64 | expand |
On Tue, Dec 05, 2023 at 02:49:57AM -0800, Xin Li wrote: > Warning: use of this parameter will taint the kernel > and may cause unknown problems. > > + fred [X86-64] > + Enable flexible return and event delivery Let's make it accept multiple options from the get-go: fred=on,disable-when,foo,bar,bla... in case we need to tweak its behavior. If it is only "fred" it will propagate this way downstream and it'll lead to confusion later when people have to update their scripts and config files when "fred" alone doesn't do what they're expecting anymore. Thx.
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 65731b060e3f..6992b392e8d3 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1526,6 +1526,9 @@ Warning: use of this parameter will taint the kernel and may cause unknown problems. + fred [X86-64] + Enable flexible return and event delivery + ftrace=[tracer] [FTRACE] will set and start the specified tracer as early as possible in order to facilitate early diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 4d4b87c6885d..68102acd63b0 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1491,6 +1491,9 @@ static void __init cpu_parse_early_param(void) char *argptr = arg, *opt; int arglen, taint = 0; + if (!cmdline_find_option_bool(boot_command_line, "fred")) + setup_clear_cpu_cap(X86_FEATURE_FRED); + #ifdef CONFIG_X86_32 if (cmdline_find_option_bool(boot_command_line, "no387")) #ifdef CONFIG_MATH_EMULATION