diff options
| author | Ingo Molnar <mingo@kernel.org> | 2015-03-03 09:34:33 +0300 |
|---|---|---|
| committer | Matt Fleming <matt.fleming@intel.com> | 2015-04-01 14:46:22 +0300 |
| commit | 23a0d4e8fa6d3a1d7fb819f79bcc0a3739c30ba9 (patch) | |
| tree | a39fccdee6dc1a89756331aac0c4db066060e96c /arch/x86/platform/efi/efi_32.c | |
| parent | fed6cefe3b6e862dcc74d07324478caa07e84eaf (diff) | |
| download | linux-23a0d4e8fa6d3a1d7fb819f79bcc0a3739c30ba9.tar.xz | |
efi: Disable interrupts around EFI calls, not in the epilog/prolog calls
Tapasweni Pathak reported that we do a kmalloc() in efi_call_phys_prolog()
on x86-64 while having interrupts disabled, which is a big no-no, as
kmalloc() can sleep.
Solve this by removing the irq disabling from the prolog/epilog calls
around EFI calls: it's unnecessary, as in this stage we are single
threaded in the boot thread, and we don't ever execute this from
interrupt contexts.
Reported-by: Tapasweni Pathak <tapaswenipathak@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Diffstat (limited to 'arch/x86/platform/efi/efi_32.c')
| -rw-r--r-- | arch/x86/platform/efi/efi_32.c | 11 |
1 files changed, 3 insertions, 8 deletions
diff --git a/arch/x86/platform/efi/efi_32.c b/arch/x86/platform/efi/efi_32.c index 40e7cda52936..abecc6e1dc90 100644 --- a/arch/x86/platform/efi/efi_32.c +++ b/arch/x86/platform/efi/efi_32.c @@ -33,11 +33,10 @@ /* * To make EFI call EFI runtime service in physical addressing mode we need - * prolog/epilog before/after the invocation to disable interrupt, to - * claim EFI runtime service handler exclusively and to duplicate a memory in - * low memory space say 0 - 3G. + * prolog/epilog before/after the invocation to claim the EFI runtime service + * handler exclusively and to duplicate a memory mapping in low memory space, + * say 0 - 3G. */ -static unsigned long efi_rt_eflags; void efi_sync_low_kernel_mappings(void) {} void __init efi_dump_pagetable(void) {} @@ -61,8 +60,6 @@ void __init efi_call_phys_prolog(void) { struct desc_ptr gdt_descr; - local_irq_save(efi_rt_eflags); - load_cr3(initial_page_table); __flush_tlb_all(); @@ -81,8 +78,6 @@ void __init efi_call_phys_epilog(void) load_cr3(swapper_pg_dir); __flush_tlb_all(); - - local_irq_restore(efi_rt_eflags); } void __init efi_runtime_mkexec(void) |