dell-wmi-sysman: New possibility to set BIOS values for Dell systems has some bugs

dell-wmi-sysman: New possibility to set BIOS values for Dell systems has some bugs

[Alexander Naumann]

I have seen this new option and wanted to test it on an R240 (OEM device).

But it is not working.


I did compile this as a module and it was loading fine. But actually it
is not.

This function call here returns 0:

ret = init_bios_attr_set_interface();


But "wmi_priv.bios_attr_wdev" is not set!

So loading the module is returning with exit code 0 (what is wrong!).
Variable "ret" should be set to 1 in this case


Also unloading the module will crash (I guess because the sys entries do
not exists).

I can send you an crashdump later on.


Any ideas why it is not working at all?

Re: dell-wmi-sysman: New possibility to set BIOS values for Dell systems has some bugs

[Alexander Naumann]

Here is the stacktrace I spoke about:


rmmod dell-wmi-sysman



[   81.809783] BUG: kernel NULL pointer dereference, address:
0000000000000048
[   81.809786] #PF: supervisor read access in kernel mode
[   81.809787] #PF: error_code(0x0000) - not-present page
[   81.809788] PGD 101fbf067 P4D 101fbf067 PUD 100e23067 PMD 0
[   81.809792] Oops: 0000 [#1] SMP
[   81.809793] CPU: 1 PID: 6833 Comm: rmmod Tainted: G           O     
5.11.0-64bit #1
[   81.809795] Hardware name:  /0DRR0P, BIOS 2.4.1 09/27/2018
[   81.809796] RIP: 0010:sysfs_remove_file_ns+0x0/0x10
[   81.809800] Code: 8b 47 08 48 8b 68 60 e8 7e e5 ff ff 48 89 df e8 06
d6 ff ff 48 89 ef 5b 5d e9 5c b7 20 00 66 66 66 2e 0f 1f 84 00 00 00 00
00 <48> 8b 7f 30 48 8b 36 e9 64 e6 ff ff 0f 1f 40 00 41 54 55 49 89 fc
[   81.809802] RSP: 0018:ffffc9000113beb0 EFLAGS: 00010246
[   81.809803] RAX: 0000000000000000 RBX: ffffffffa01b6dc0 RCX:
0000000000000000
[   81.809804] RDX: 0000000000000000 RSI: ffffffffa01b6060 RDI:
0000000000000018
[   81.809805] RBP: 0000000000000081 R08: 0000000000000000 R09:
000000000000006e
[   81.809806] R10: ff6d606c7278725e R11: 006e616d7379735f R12:
0000000000000880
[   81.809807] R13: 0000000000000880 R14: 0000000000000000 R15:
0000000000000000
[   81.809808] FS:  0000000000000000(0000) GS:ffff88846ed00000(0063)
knlGS:00000000f7d21940
[   81.809810] CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
[   81.809811] CR2: 0000000000000048 CR3: 0000000100e20001 CR4:
00000000003706e0
[   81.809812] Call Trace:
[   81.809814]  release_attributes_data+0x19/0xa3 [dell_wmi_sysman]
[   81.809817]  sysman_exit+0x5/0xd8b [dell_wmi_sysman]
[   81.809819]  __ia32_sys_delete_module+0x16b/0x240
[   81.809822]  __do_fast_syscall_32+0x56/0x80
[   81.809826]  do_fast_syscall_32+0x2f/0x70
[   81.809828]  entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
[   81.809830] RIP: 0023:0xf7edc549
[   81.809831] Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03
74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd
80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
[   81.809833] RSP: 002b:00000000ffe08bc8 EFLAGS: 00000246 ORIG_RAX:
0000000000000081
[   81.809834] RAX: ffffffffffffffda RBX: 00000000ffe08c00 RCX:
0000000000000880
[   81.809835] RDX: 00000000ffe0b454 RSI: 0000000000000003 RDI:
00000000ffe08c00
[   81.809836] RBP: 00000000ffe0b4a8 R08: 0000000000000000 R09:
0000000000000000
[   81.809837] R10: 0000000000000000 R11: 0000000000000000 R12:
0000000000000000
[   81.809838] R13: 0000000000000000 R14: 0000000000000000 R15:
0000000000000000
[   81.809839] Modules linked in: dell_wmi_sysman(O-) wmi
scsi_transport_fc scsi_dh_rdac scsi_dh_emc scsi_dh_alua scsi_dh_hp_sw
xt_nat xt_REDIRECT iptable_nat nf_nat ipt_REJECT nf_reject_ipv4 xt_state
iptable_filter ip_tables thermal fan ipv6 fuse dm_snapshot dm_bufio
dm_round_robin dm_multipath psmouse ipmi_ssif pcspkr acpi_ipmi iTCO_wdt
iTCO_vendor_support ipmi_si ipmi_msghandler ac intel_pch_thermal
ie31200_edac [last unloaded: qla2xxx]
[   81.809857] CR2: 0000000000000048
[   81.809859] ---[ end trace 175f62942dce486b ]---
[   81.809859] RIP: 0010:sysfs_remove_file_ns+0x0/0x10
[   81.809861] Code: 8b 47 08 48 8b 68 60 e8 7e e5 ff ff 48 89 df e8 06
d6 ff ff 48 89 ef 5b 5d e9 5c b7 20 00 66 66 66 2e 0f 1f 84 00 00 00 00
00 <48> 8b 7f 30 48 8b 36 e9 64 e6 ff ff 0f 1f 40 00 41 54 55 49 89 fc
[   81.809863] RSP: 0018:ffffc9000113beb0 EFLAGS: 00010246
[   81.809864] RAX: 0000000000000000 RBX: ffffffffa01b6dc0 RCX:
0000000000000000
[   81.809865] RDX: 0000000000000000 RSI: ffffffffa01b6060 RDI:
0000000000000018
[   81.809866] RBP: 0000000000000081 R08: 0000000000000000 R09:
000000000000006e
[   81.809866] R10: ff6d606c7278725e R11: 006e616d7379735f R12:
0000000000000880
[   81.809867] R13: 0000000000000880 R14: 0000000000000000 R15:
0000000000000000
[   81.809868] FS:  0000000000000000(0000) GS:ffff88846ed00000(0063)
knlGS:00000000f7d21940
[   81.809869] CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
[   81.809870] CR2: 0000000000000048 CR3: 0000000100e20001 CR4:
00000000003706e0


Am 18.02.21 um 11:57 schrieb Alexander Naumann:
> I have seen this new option and wanted to test it on an R240 (OEM device).
>
> But it is not working.
>
>
> I did compile this as a module and it was loading fine. But actually it
> is not.
>
> This function call here returns 0:
>
> ret = init_bios_attr_set_interface();
>
>
> But "wmi_priv.bios_attr_wdev" is not set!
>
> So loading the module is returning with exit code 0 (what is wrong!).
> Variable "ret" should be set to 1 in this case
>
>
> Also unloading the module will crash (I guess because the sys entries do
> not exists).
>
> I can send you an crashdump later on.
>
>
> Any ideas why it is not working at all?
>
>
>
>

RE: dell-wmi-sysman: New possibility to set BIOS values for Dell systems has some bugs

[Limonciello, Mario]

Thanks for the report and stack trace.  I've sent a patch back to the mailing
list to prevent this failure.

I'm sorry to be the bearer of bad news, but the feature is not supported by
your R240.  It's currently supported by newer workstations.
I don't see a reason why it couldn't be supported on a server from the driver's
architecture, but often things that can be controlled through this type of
interface are already managed by out of band management on servers.

If your organization sees it as useful to you from a server perspective, please bring
that request back through your sales channel to discuss with engineering
viability to enable the firmware support needed for it on servers as well.

> -----Original Message-----
> From: Alexander Naumann <alexandernaumann@gmx.de>
> Sent: Thursday, February 18, 2021 7:54
> To: Bharathi, Divya; Limonciello, Mario
> Cc: platform-driver-x86@vger.kernel.org
> Subject: Re: dell-wmi-sysman: New possibility to set BIOS values for Dell
> systems has some bugs
> 
> 
> [EXTERNAL EMAIL]
> 
> Here is the stacktrace I spoke about:
> 
> 
> rmmod dell-wmi-sysman
> 
> 
> 
> [   81.809783] BUG: kernel NULL pointer dereference, address:
> 0000000000000048
> [   81.809786] #PF: supervisor read access in kernel mode
> [   81.809787] #PF: error_code(0x0000) - not-present page
> [   81.809788] PGD 101fbf067 P4D 101fbf067 PUD 100e23067 PMD 0
> [   81.809792] Oops: 0000 [#1] SMP
> [   81.809793] CPU: 1 PID: 6833 Comm: rmmod Tainted: G           O
> 5.11.0-64bit #1
> [   81.809795] Hardware name:  /0DRR0P, BIOS 2.4.1 09/27/2018
> [   81.809796] RIP: 0010:sysfs_remove_file_ns+0x0/0x10
> [   81.809800] Code: 8b 47 08 48 8b 68 60 e8 7e e5 ff ff 48 89 df e8 06
> d6 ff ff 48 89 ef 5b 5d e9 5c b7 20 00 66 66 66 2e 0f 1f 84 00 00 00 00
> 00 <48> 8b 7f 30 48 8b 36 e9 64 e6 ff ff 0f 1f 40 00 41 54 55 49 89 fc
> [   81.809802] RSP: 0018:ffffc9000113beb0 EFLAGS: 00010246
> [   81.809803] RAX: 0000000000000000 RBX: ffffffffa01b6dc0 RCX:
> 0000000000000000
> [   81.809804] RDX: 0000000000000000 RSI: ffffffffa01b6060 RDI:
> 0000000000000018
> [   81.809805] RBP: 0000000000000081 R08: 0000000000000000 R09:
> 000000000000006e
> [   81.809806] R10: ff6d606c7278725e R11: 006e616d7379735f R12:
> 0000000000000880
> [   81.809807] R13: 0000000000000880 R14: 0000000000000000 R15:
> 0000000000000000
> [   81.809808] FS:  0000000000000000(0000) GS:ffff88846ed00000(0063)
> knlGS:00000000f7d21940
> [   81.809810] CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
> [   81.809811] CR2: 0000000000000048 CR3: 0000000100e20001 CR4:
> 00000000003706e0
> [   81.809812] Call Trace:
> [   81.809814]  release_attributes_data+0x19/0xa3 [dell_wmi_sysman]
> [   81.809817]  sysman_exit+0x5/0xd8b [dell_wmi_sysman]
> [   81.809819]  __ia32_sys_delete_module+0x16b/0x240
> [   81.809822]  __do_fast_syscall_32+0x56/0x80
> [   81.809826]  do_fast_syscall_32+0x2f/0x70
> [   81.809828]  entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
> [   81.809830] RIP: 0023:0xf7edc549
> [   81.809831] Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03
> 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd
> 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
> [   81.809833] RSP: 002b:00000000ffe08bc8 EFLAGS: 00000246 ORIG_RAX:
> 0000000000000081
> [   81.809834] RAX: ffffffffffffffda RBX: 00000000ffe08c00 RCX:
> 0000000000000880
> [   81.809835] RDX: 00000000ffe0b454 RSI: 0000000000000003 RDI:
> 00000000ffe08c00
> [   81.809836] RBP: 00000000ffe0b4a8 R08: 0000000000000000 R09:
> 0000000000000000
> [   81.809837] R10: 0000000000000000 R11: 0000000000000000 R12:
> 0000000000000000
> [   81.809838] R13: 0000000000000000 R14: 0000000000000000 R15:
> 0000000000000000
> [   81.809839] Modules linked in: dell_wmi_sysman(O-) wmi
> scsi_transport_fc scsi_dh_rdac scsi_dh_emc scsi_dh_alua scsi_dh_hp_sw
> xt_nat xt_REDIRECT iptable_nat nf_nat ipt_REJECT nf_reject_ipv4 xt_state
> iptable_filter ip_tables thermal fan ipv6 fuse dm_snapshot dm_bufio
> dm_round_robin dm_multipath psmouse ipmi_ssif pcspkr acpi_ipmi iTCO_wdt
> iTCO_vendor_support ipmi_si ipmi_msghandler ac intel_pch_thermal
> ie31200_edac [last unloaded: qla2xxx]
> [   81.809857] CR2: 0000000000000048
> [   81.809859] ---[ end trace 175f62942dce486b ]---
> [   81.809859] RIP: 0010:sysfs_remove_file_ns+0x0/0x10
> [   81.809861] Code: 8b 47 08 48 8b 68 60 e8 7e e5 ff ff 48 89 df e8 06
> d6 ff ff 48 89 ef 5b 5d e9 5c b7 20 00 66 66 66 2e 0f 1f 84 00 00 00 00
> 00 <48> 8b 7f 30 48 8b 36 e9 64 e6 ff ff 0f 1f 40 00 41 54 55 49 89 fc
> [   81.809863] RSP: 0018:ffffc9000113beb0 EFLAGS: 00010246
> [   81.809864] RAX: 0000000000000000 RBX: ffffffffa01b6dc0 RCX:
> 0000000000000000
> [   81.809865] RDX: 0000000000000000 RSI: ffffffffa01b6060 RDI:
> 0000000000000018
> [   81.809866] RBP: 0000000000000081 R08: 0000000000000000 R09:
> 000000000000006e
> [   81.809866] R10: ff6d606c7278725e R11: 006e616d7379735f R12:
> 0000000000000880
> [   81.809867] R13: 0000000000000880 R14: 0000000000000000 R15:
> 0000000000000000
> [   81.809868] FS:  0000000000000000(0000) GS:ffff88846ed00000(0063)
> knlGS:00000000f7d21940
> [   81.809869] CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
> [   81.809870] CR2: 0000000000000048 CR3: 0000000100e20001 CR4:
> 00000000003706e0
> 
> 
> Am 18.02.21 um 11:57 schrieb Alexander Naumann:
> > I have seen this new option and wanted to test it on an R240 (OEM device).
> >
> > But it is not working.
> >
> >
> > I did compile this as a module and it was loading fine. But actually it
> > is not.
> >
> > This function call here returns 0:
> >
> > ret = init_bios_attr_set_interface();
> >
> >
> > But "wmi_priv.bios_attr_wdev" is not set!
> >
> > So loading the module is returning with exit code 0 (what is wrong!).
> > Variable "ret" should be set to 1 in this case
> >
> >
> > Also unloading the module will crash (I guess because the sys entries do
> > not exists).
> >
> > I can send you an crashdump later on.
> >
> >
> > Any ideas why it is not working at all?
> >
> >
> >
> >