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| author | Xin Li (Intel) <xin@zytor.com> | 2024-07-09 17:40:47 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2024-08-13 21:59:21 +0200 |
| commit | 73270c1f2369fb37683121ebe097cd37172602b6 (patch) | |
| tree | 3f8968a3e4c5a021c64e3fa4da8dc8d036d46e03 /arch/x86/kernel | |
| parent | x86/fred: Parse cmdline param "fred=" in cpu_parse_early_param() (diff) | |
| download | linux-73270c1f2369fb37683121ebe097cd37172602b6.tar.xz linux-73270c1f2369fb37683121ebe097cd37172602b6.zip | |
x86/fred: Move FRED RSP initialization into a separate function
To enable FRED earlier, move the RSP initialization out of
cpu_init_fred_exceptions() into cpu_init_fred_rsps().
This is required as the FRED RSP initialization depends on the availability
of the CPU entry areas which are set up late in trap_init(),
No functional change intended. Marked with Fixes as it's a depedency for
the real fix.
Fixes: 14619d912b65 ("x86/fred: FRED entry/exit and dispatch code")
Signed-off-by: Xin Li (Intel) <xin@zytor.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20240709154048.3543361-3-xin@zytor.com
Diffstat (limited to 'arch/x86/kernel')
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 6 | ||||
| -rw-r--r-- | arch/x86/kernel/fred.c | 28 |
2 files changed, 23 insertions, 11 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 10a5402d8297..6de12b3c1b04 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -2195,10 +2195,12 @@ void cpu_init_exception_handling(void) /* GHCB needs to be setup to handle #VC. */ setup_ghcb(); - if (cpu_feature_enabled(X86_FEATURE_FRED)) + if (cpu_feature_enabled(X86_FEATURE_FRED)) { cpu_init_fred_exceptions(); - else + cpu_init_fred_rsps(); + } else { load_current_idt(); + } } /* diff --git a/arch/x86/kernel/fred.c b/arch/x86/kernel/fred.c index 4bcd8791ad96..99a134fcd5bf 100644 --- a/arch/x86/kernel/fred.c +++ b/arch/x86/kernel/fred.c @@ -32,6 +32,25 @@ void cpu_init_fred_exceptions(void) FRED_CONFIG_INT_STKLVL(0) | FRED_CONFIG_ENTRYPOINT(asm_fred_entrypoint_user)); + wrmsrl(MSR_IA32_FRED_STKLVLS, 0); + wrmsrl(MSR_IA32_FRED_RSP0, 0); + wrmsrl(MSR_IA32_FRED_RSP1, 0); + wrmsrl(MSR_IA32_FRED_RSP2, 0); + wrmsrl(MSR_IA32_FRED_RSP3, 0); + + /* Enable FRED */ + cr4_set_bits(X86_CR4_FRED); + /* Any further IDT use is a bug */ + idt_invalidate(); + + /* Use int $0x80 for 32-bit system calls in FRED mode */ + setup_clear_cpu_cap(X86_FEATURE_SYSENTER32); + setup_clear_cpu_cap(X86_FEATURE_SYSCALL32); +} + +/* Must be called after setup_cpu_entry_areas() */ +void cpu_init_fred_rsps(void) +{ /* * The purpose of separate stacks for NMI, #DB and #MC *in the kernel* * (remember that user space faults are always taken on stack level 0) @@ -47,13 +66,4 @@ void cpu_init_fred_exceptions(void) wrmsrl(MSR_IA32_FRED_RSP1, __this_cpu_ist_top_va(DB)); wrmsrl(MSR_IA32_FRED_RSP2, __this_cpu_ist_top_va(NMI)); wrmsrl(MSR_IA32_FRED_RSP3, __this_cpu_ist_top_va(DF)); - - /* Enable FRED */ - cr4_set_bits(X86_CR4_FRED); - /* Any further IDT use is a bug */ - idt_invalidate(); - - /* Use int $0x80 for 32-bit system calls in FRED mode */ - setup_clear_cpu_cap(X86_FEATURE_SYSENTER32); - setup_clear_cpu_cap(X86_FEATURE_SYSCALL32); } |