efi_pstore: Remove a logic erasing entries from a write callback to hold multiple logs
[Issue]
Currently, efi_pstore driver simply overwrites existing panic messages in NVRAM.
So, in the following scenario, we will lose 1st panic messages.
1. kernel panics.
2. efi_pstore is kicked and writes panic messages to NVRAM.
3. system reboots.
4. kernel panics again before a user checks the 1st panic messages in NVRAM.
[Solution]
A reasonable solution to fix the issue is just holding multiple logs without erasing
existing entries.
This patch removes a logic erasing existing entries in a write callback
because the logic is not needed in the write callback to support holding multiple logs.
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Acked-by: Mike Waychison <mikew@google.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c
index bee14cc..fbe9202 100644
--- a/drivers/firmware/efivars.c
+++ b/drivers/firmware/efivars.c
@@ -701,18 +701,13 @@
unsigned int part, size_t size, struct pstore_info *psi)
{
char name[DUMP_NAME_LEN];
- char stub_name[DUMP_NAME_LEN];
efi_char16_t efi_name[DUMP_NAME_LEN];
efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
struct efivars *efivars = psi->data;
- struct efivar_entry *entry, *found = NULL;
int i, ret = 0;
u64 storage_space, remaining_space, max_variable_size;
efi_status_t status = EFI_NOT_FOUND;
- sprintf(stub_name, "dump-type%u-%u-", type, part);
- sprintf(name, "%s%lu", stub_name, get_seconds());
-
spin_lock(&efivars->lock);
/*
@@ -730,35 +725,8 @@
return -ENOSPC;
}
- for (i = 0; i < DUMP_NAME_LEN; i++)
- efi_name[i] = stub_name[i];
-
- /*
- * Clean up any entries with the same name
- */
-
- list_for_each_entry(entry, &efivars->list, list) {
- get_var_data_locked(efivars, &entry->var);
-
- if (efi_guidcmp(entry->var.VendorGuid, vendor))
- continue;
- if (utf16_strncmp(entry->var.VariableName, efi_name,
- utf16_strlen(efi_name)))
- continue;
- /* Needs to be a prefix */
- if (entry->var.VariableName[utf16_strlen(efi_name)] == 0)
- continue;
-
- /* found */
- found = entry;
- efivars->ops->set_variable(entry->var.VariableName,
- &entry->var.VendorGuid,
- PSTORE_EFI_ATTRIBUTES,
- 0, NULL);
- }
-
- if (found)
- list_del(&found->list);
+ sprintf(name, "dump-type%u-%u-%lu", type, part,
+ get_seconds());
for (i = 0; i < DUMP_NAME_LEN; i++)
efi_name[i] = name[i];
@@ -768,9 +736,6 @@
spin_unlock(&efivars->lock);
- if (found)
- efivar_unregister(found);
-
if (size)
ret = efivar_create_sysfs_entry(efivars,
utf16_strsize(efi_name,