From 85c90716aae49f05a67c757df7b8c413256103f2 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Tue, 30 Apr 2013 10:43:12 +0300 Subject: efi: locking fix in efivar_entry_set_safe() The intent is that if we aren't allowed to block because we're in an NMI or an emergency then we only take the lock if it is uncontended. Part of the problem is the test is reversed so we return -EBUSY if we acquire the lock. Signed-off-by: Dan Carpenter Signed-off-by: Matt Fleming --- drivers/firmware/efi/vars.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'drivers/firmware') diff --git a/drivers/firmware/efi/vars.c b/drivers/firmware/efi/vars.c index 96d328b21c3e..391c67b182d9 100644 --- a/drivers/firmware/efi/vars.c +++ b/drivers/firmware/efi/vars.c @@ -622,10 +622,12 @@ int efivar_entry_set_safe(efi_char16_t *name, efi_guid_t vendor, u32 attributes, if (!ops->query_variable_store) return -ENOSYS; - if (!block && spin_trylock_irqsave(&__efivars->lock, flags)) - return -EBUSY; - else + if (!block) { + if (!spin_trylock_irqsave(&__efivars->lock, flags)) + return -EBUSY; + } else { spin_lock_irqsave(&__efivars->lock, flags); + } status = check_var_size(attributes, size + ucs2_strsize(name, 1024)); if (status != EFI_SUCCESS) { -- cgit v1.2.3