Hi Jan,
On Fri, 9 Jun 2023 at 09:40, Jan Kiszka jan.kiszka@siemens.com wrote:
On 09.06.23 08:34, Ilias Apalodimas wrote:
Hi Jan,
[...]
--- a/drivers/firmware/efi/vars.c +++ b/drivers/firmware/efi/vars.c @@ -123,7 +123,7 @@ EXPORT_SYMBOL_GPL(efivars_unregister);
bool efivar_supports_writes(void) {
return __efivars && __efivars->ops->set_variable;
return __efivars && __efivars->ops->set_variable != set_variable_int;} EXPORT_SYMBOL_GPL(efivar_supports_writes);
diff --git a/fs/efivarfs/super.c b/fs/efivarfs/super.c index e028fafa04f3..e40b5c4c5106 100644 --- a/fs/efivarfs/super.c +++ b/fs/efivarfs/super.c @@ -242,9 +242,6 @@ static int efivarfs_fill_super(struct super_block *sb, struct fs_context *fc) sb->s_d_op = &efivarfs_d_ops; sb->s_time_gran = 1;
if (!efivar_supports_writes())sb->s_flags |= SB_RDONLY;inode = efivarfs_get_inode(sb, NULL, S_IFDIR | 0755, 0, true); if (!inode) return -ENOMEM;diff --git a/include/linux/efi.h b/include/linux/efi.h index 58d1c271d3b0..ec0ac6ef50a3 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -1084,6 +1084,10 @@ int efivars_register(struct efivars *efivars, const struct efivar_operations *ops); int efivars_unregister(struct efivars *efivars);
+efi_status_t set_variable_int(efi_char16_t *name, efi_guid_t *vendor,
u32 attributes, unsigned long data_size,void *data);void efivars_generic_ops_register(void); void efivars_generic_ops_unregister(void);
Thanks /Ilias
As just written in my other reply: The root cause is the dependency on tee-supplicant daemon. That needs to be resolved, and then also r/w mounting will just work.
That's partially true. If we solve the dependency your problem will go away only if everything gets compiled as built in. But if you have them as modules there's still a chance you mount the efivarfs before installing all the modules. In that case, you'll end up with the same problem no?
Obviously, this will need proper probing of the TA services in the proper order so that the STMM driver is pulled in before efivarfs gets used.
That's why I think this patch (or a variation of it) is useful. It solves the kernel panic you are seeing if you remount the efivarfs as RW and It unifies the way the kernel responds to userspace no matter what the firmware does with its setvariableRT service.
I'm not against fixes crashes, but the r/w issue is a different thing IMHO.
Fair enough, but if we want to fix the crash only I think there's a better way to do it. I'll cook some patches and send them over
Thanks /Ilias
Jan
-- Siemens AG, Technology Competence Center Embedded Linux