Hi,
with v5.3-rc1 I'm hitting the following BUG() when trying to load the
gpio-backlight module:
kernel BUG at kernel/module.c:1919!
Internal error: Oops - BUG: 0 [#1] PREEMPT ARM
Modules linked in:
CPU: 0 PID: 1 Comm: systemd Tainted: G W
5.2.0-rc2-00005-g7dabaa5ce05a #19
Hardware name: DaVinci DA850/OMAP-L138/AM18x EVM
PC is at frob_text.constprop.16+0x2c/0x34
LR is at load_module+0x1888/0x21b4
pc : [<c0081bbc>] lr : [<c0083c4c>] psr: 20000013
sp : c6837e58 ip : c6b4fa80 fp : bf00574c
r10: c0601008 r9 : bf005740 r8 : c0493e38
r7 : c00807f8 r6 : 00000000 r5 : 00000001 r4 : c6837f38
r3 : 00000fff r2 : bf000000 r1 : 00004b80 r0 : bf005818
Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
Control: 0005317f Table: c6b78000 DAC: 00000051
Process systemd (pid: 1, stack limit = 0x(ptrval))
Stack: (0xc6837e58 to 0xc6838000)
7e40: bf005740 c6492a90
7e60: 00000001 c6bf5788 00000003 c6837f38 bf0058c0 bf0058a8 bf00a495 c0493e38
7e80: 00000000 c05368c0 00000001 00000000 c0580030 c0574b28 00000000 00000000
7ea0: 00000000 00000000 00000000 00000000 6e72656b 00006c65 00000000 00000000
7ec0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
7ee0: 00000000 00000000 00000000 aefb2bb8 7fffffff c0601008 00000000 00000004
7f00: b6cee714 c00091e4 c6836000 00000000 005bc668 c00847b0 7fffffff 00000000
7f20: 00000003 00000000 0000b2d0 c884e000 0000b2d0 00000000 c8852dcb c88533a0
7f40: c884e000 0000b2d0 c8858cb8 c8858b34 c88568d4 000058c0 00006190 000023b8
7f60: 00006713 00000000 00000000 00000000 000023a8 00000024 00000025 00000019
7f80: 0000001d 00000011 00000000 aefb2bb8 00000000 00000000 00000000 00000000
7fa0: 0000017b c0009000 00000000 00000000 00000004 b6cee714 00000000 00000000
7fc0: 00000000 00000000 00000000 0000017b 00000000 00000000 00000001 005bc668
7fe0: be907b00 be907af0 b6ce66b0 b6c3fac0 60000010 00000004 00000000 00000000
[<c0081bbc>] (frob_text.constprop.16) from [<c0083c4c>]
(load_module+0x1888/0x21b4)
[<c0083c4c>] (load_module) from [<c00847b0>] (sys_finit_module+0xbc/0xdc)
[<c00847b0>] (sys_finit_module) from [<c0009000>] (ret_fast_syscall+0x0/0x50)
Exception stack(0xc6837fa8 to 0xc6837ff0)
7fa0: 00000000 00000000 00000004 b6cee714 00000000 00000000
7fc0: 00000000 00000000 00000000 0000017b 00000000 00000000 00000001 005bc668
7fe0: be907b00 be907af0 b6ce66b0 b6c3fac0
Code: e1a01621 e1a00002 eafe4531 e7f001f2 (e7f001f2)
---[ end trace 2cbefb0005882c52 ]---
Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
---[ end Kernel panic - not syncing: Attempted to kill init!
exitcode=0x0000000b ]---
I bisected it to commit 06bd260e836d ("modules: fix BUG when load
module with rodata=n") with commit 7dabaa5ce05a ("modules: fix compile
error if don't have strict module rwx") on top to make it build.
Let me know if you need me to provide more info.
Best regards,
Bartosz Golaszewski
pon., 22 lip 2019 o 14:12 Bartosz Golaszewski <[email protected]> napisał(a):
>
> Hi,
>
> with v5.3-rc1 I'm hitting the following BUG() when trying to load the
> gpio-backlight module:
>
> kernel BUG at kernel/module.c:1919!
> Internal error: Oops - BUG: 0 [#1] PREEMPT ARM
> Modules linked in:
> CPU: 0 PID: 1 Comm: systemd Tainted: G W
> 5.2.0-rc2-00005-g7dabaa5ce05a #19
> Hardware name: DaVinci DA850/OMAP-L138/AM18x EVM
> PC is at frob_text.constprop.16+0x2c/0x34
> LR is at load_module+0x1888/0x21b4
> pc : [<c0081bbc>] lr : [<c0083c4c>] psr: 20000013
> sp : c6837e58 ip : c6b4fa80 fp : bf00574c
> r10: c0601008 r9 : bf005740 r8 : c0493e38
> r7 : c00807f8 r6 : 00000000 r5 : 00000001 r4 : c6837f38
> r3 : 00000fff r2 : bf000000 r1 : 00004b80 r0 : bf005818
> Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
> Control: 0005317f Table: c6b78000 DAC: 00000051
> Process systemd (pid: 1, stack limit = 0x(ptrval))
> Stack: (0xc6837e58 to 0xc6838000)
> 7e40: bf005740 c6492a90
> 7e60: 00000001 c6bf5788 00000003 c6837f38 bf0058c0 bf0058a8 bf00a495 c0493e38
> 7e80: 00000000 c05368c0 00000001 00000000 c0580030 c0574b28 00000000 00000000
> 7ea0: 00000000 00000000 00000000 00000000 6e72656b 00006c65 00000000 00000000
> 7ec0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> 7ee0: 00000000 00000000 00000000 aefb2bb8 7fffffff c0601008 00000000 00000004
> 7f00: b6cee714 c00091e4 c6836000 00000000 005bc668 c00847b0 7fffffff 00000000
> 7f20: 00000003 00000000 0000b2d0 c884e000 0000b2d0 00000000 c8852dcb c88533a0
> 7f40: c884e000 0000b2d0 c8858cb8 c8858b34 c88568d4 000058c0 00006190 000023b8
> 7f60: 00006713 00000000 00000000 00000000 000023a8 00000024 00000025 00000019
> 7f80: 0000001d 00000011 00000000 aefb2bb8 00000000 00000000 00000000 00000000
> 7fa0: 0000017b c0009000 00000000 00000000 00000004 b6cee714 00000000 00000000
> 7fc0: 00000000 00000000 00000000 0000017b 00000000 00000000 00000001 005bc668
> 7fe0: be907b00 be907af0 b6ce66b0 b6c3fac0 60000010 00000004 00000000 00000000
> [<c0081bbc>] (frob_text.constprop.16) from [<c0083c4c>]
> (load_module+0x1888/0x21b4)
> [<c0083c4c>] (load_module) from [<c00847b0>] (sys_finit_module+0xbc/0xdc)
> [<c00847b0>] (sys_finit_module) from [<c0009000>] (ret_fast_syscall+0x0/0x50)
> Exception stack(0xc6837fa8 to 0xc6837ff0)
> 7fa0: 00000000 00000000 00000004 b6cee714 00000000 00000000
> 7fc0: 00000000 00000000 00000000 0000017b 00000000 00000000 00000001 005bc668
> 7fe0: be907b00 be907af0 b6ce66b0 b6c3fac0
> Code: e1a01621 e1a00002 eafe4531 e7f001f2 (e7f001f2)
> ---[ end trace 2cbefb0005882c52 ]---
> Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
> ---[ end Kernel panic - not syncing: Attempted to kill init!
> exitcode=0x0000000b ]---
>
> I bisected it to commit 06bd260e836d ("modules: fix BUG when load
> module with rodata=n") with commit 7dabaa5ce05a ("modules: fix compile
> error if don't have strict module rwx") on top to make it build.
>
I got the commit hashes wrong, because I was playing with a modified
tree. They are 2eef1399a866 ("modules: fix BUG when load module with
rodata=n") and 93651f80dcb6 ("modules: fix compile error if don't have
strict module rwx") respectively.
Bart
> Let me know if you need me to provide more info.
>
> Best regards,
> Bartosz Golaszewski
+++ Bartosz Golaszewski [22/07/19 14:12 +0200]:
>Hi,
>
>with v5.3-rc1 I'm hitting the following BUG() when trying to load the
>gpio-backlight module:
>
>kernel BUG at kernel/module.c:1919!
>Internal error: Oops - BUG: 0 [#1] PREEMPT ARM
>Modules linked in:
>CPU: 0 PID: 1 Comm: systemd Tainted: G W
>5.2.0-rc2-00005-g7dabaa5ce05a #19
>Hardware name: DaVinci DA850/OMAP-L138/AM18x EVM
>PC is at frob_text.constprop.16+0x2c/0x34
>LR is at load_module+0x1888/0x21b4
>pc : [<c0081bbc>] lr : [<c0083c4c>] psr: 20000013
>sp : c6837e58 ip : c6b4fa80 fp : bf00574c
>r10: c0601008 r9 : bf005740 r8 : c0493e38
>r7 : c00807f8 r6 : 00000000 r5 : 00000001 r4 : c6837f38
>r3 : 00000fff r2 : bf000000 r1 : 00004b80 r0 : bf005818
>Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
>Control: 0005317f Table: c6b78000 DAC: 00000051
>Process systemd (pid: 1, stack limit = 0x(ptrval))
>Stack: (0xc6837e58 to 0xc6838000)
>7e40: bf005740 c6492a90
>7e60: 00000001 c6bf5788 00000003 c6837f38 bf0058c0 bf0058a8 bf00a495 c0493e38
>7e80: 00000000 c05368c0 00000001 00000000 c0580030 c0574b28 00000000 00000000
>7ea0: 00000000 00000000 00000000 00000000 6e72656b 00006c65 00000000 00000000
>7ec0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
>7ee0: 00000000 00000000 00000000 aefb2bb8 7fffffff c0601008 00000000 00000004
>7f00: b6cee714 c00091e4 c6836000 00000000 005bc668 c00847b0 7fffffff 00000000
>7f20: 00000003 00000000 0000b2d0 c884e000 0000b2d0 00000000 c8852dcb c88533a0
>7f40: c884e000 0000b2d0 c8858cb8 c8858b34 c88568d4 000058c0 00006190 000023b8
>7f60: 00006713 00000000 00000000 00000000 000023a8 00000024 00000025 00000019
>7f80: 0000001d 00000011 00000000 aefb2bb8 00000000 00000000 00000000 00000000
>7fa0: 0000017b c0009000 00000000 00000000 00000004 b6cee714 00000000 00000000
>7fc0: 00000000 00000000 00000000 0000017b 00000000 00000000 00000001 005bc668
>7fe0: be907b00 be907af0 b6ce66b0 b6c3fac0 60000010 00000004 00000000 00000000
>[<c0081bbc>] (frob_text.constprop.16) from [<c0083c4c>]
>(load_module+0x1888/0x21b4)
>[<c0083c4c>] (load_module) from [<c00847b0>] (sys_finit_module+0xbc/0xdc)
>[<c00847b0>] (sys_finit_module) from [<c0009000>] (ret_fast_syscall+0x0/0x50)
>Exception stack(0xc6837fa8 to 0xc6837ff0)
>7fa0: 00000000 00000000 00000004 b6cee714 00000000 00000000
>7fc0: 00000000 00000000 00000000 0000017b 00000000 00000000 00000001 005bc668
>7fe0: be907b00 be907af0 b6ce66b0 b6c3fac0
>Code: e1a01621 e1a00002 eafe4531 e7f001f2 (e7f001f2)
>---[ end trace 2cbefb0005882c52 ]---
>Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
>---[ end Kernel panic - not syncing: Attempted to kill init!
>exitcode=0x0000000b ]---
>
>I bisected it to commit 06bd260e836d ("modules: fix BUG when load
>module with rodata=n") with commit 7dabaa5ce05a ("modules: fix compile
>error if don't have strict module rwx") on top to make it build.
>
>Let me know if you need me to provide more info.
>
>Best regards,
>Bartosz Golaszewski
Hi Bartosz,
Thanks for reporting this, I was able to reproduce this on qemu.
This is due to hitting the BUG_ON() in frob_text() due to layout->base
and/or layout->text_size not being page-aligned. These values are
always page-aligned when CONFIG_STRICT_MODULE_RWX=y, but in commit
2eef1399a86 ("modules: fix BUG when load module with rodata=n"), the
frob_text()+set_memory_x() calls got moved *outside* of the
STRICT_MODULE_RWX block since some arches (like x86 and arm64)
allocate non-executable module memory via module_alloc(), so naturally
the module text needed to be made executable at a later stage of
load_module(), regardless of whether STRICT_MODULE_RWX is set or not.
In your case, you must've had CONFIG_STRICT_MODULE_RWX=n and so we
were calling frob_text() with non-page-aligned values, triggering the
BUG_ON().
In any case, could you please try and see if the following patch fixes
the issue for you?
diff --git a/kernel/module.c b/kernel/module.c
index 5933395af9a0..cd8df516666d 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -64,14 +64,9 @@
/*
* Modules' sections will be aligned on page boundaries
- * to ensure complete separation of code and data, but
- * only when CONFIG_STRICT_MODULE_RWX=y
+ * to ensure complete separation of code and data
*/
-#ifdef CONFIG_STRICT_MODULE_RWX
# define debug_align(X) ALIGN(X, PAGE_SIZE)
-#else
-# define debug_align(X) (X)
-#endif
/* If this is set, the section belongs in the init part of the module */
#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
On 7/22/19 11:10 AM, Jessica Yu wrote:
> +++ Bartosz Golaszewski [22/07/19 14:12 +0200]:
>> Hi,
>>
>> with v5.3-rc1 I'm hitting the following BUG() when trying to load the
>> gpio-backlight module:
>>
>> kernel BUG at kernel/module.c:1919!
>> Internal error: Oops - BUG: 0 [#1] PREEMPT ARM
>> Modules linked in:
>> CPU: 0 PID: 1 Comm: systemd Tainted: G W
>> 5.2.0-rc2-00005-g7dabaa5ce05a #19
>> Hardware name: DaVinci DA850/OMAP-L138/AM18x EVM
>> PC is at frob_text.constprop.16+0x2c/0x34
>> LR is at load_module+0x1888/0x21b4
>> pc : [<c0081bbc>] lr : [<c0083c4c>] psr: 20000013
>> sp : c6837e58 ip : c6b4fa80 fp : bf00574c
>> r10: c0601008 r9 : bf005740 r8 : c0493e38
>> r7 : c00807f8 r6 : 00000000 r5 : 00000001 r4 : c6837f38
>> r3 : 00000fff r2 : bf000000 r1 : 00004b80 r0 : bf005818
>> Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
>> Control: 0005317f Table: c6b78000 DAC: 00000051
>> Process systemd (pid: 1, stack limit = 0x(ptrval))
>> Stack: (0xc6837e58 to 0xc6838000)
>> 7e40: bf005740 c6492a90
>> 7e60: 00000001 c6bf5788 00000003 c6837f38 bf0058c0 bf0058a8 bf00a495 c0493e38
>> 7e80: 00000000 c05368c0 00000001 00000000 c0580030 c0574b28 00000000 00000000
>> 7ea0: 00000000 00000000 00000000 00000000 6e72656b 00006c65 00000000 00000000
>> 7ec0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
>> 7ee0: 00000000 00000000 00000000 aefb2bb8 7fffffff c0601008 00000000 00000004
>> 7f00: b6cee714 c00091e4 c6836000 00000000 005bc668 c00847b0 7fffffff 00000000
>> 7f20: 00000003 00000000 0000b2d0 c884e000 0000b2d0 00000000 c8852dcb c88533a0
>> 7f40: c884e000 0000b2d0 c8858cb8 c8858b34 c88568d4 000058c0 00006190 000023b8
>> 7f60: 00006713 00000000 00000000 00000000 000023a8 00000024 00000025 00000019
>> 7f80: 0000001d 00000011 00000000 aefb2bb8 00000000 00000000 00000000 00000000
>> 7fa0: 0000017b c0009000 00000000 00000000 00000004 b6cee714 00000000 00000000
>> 7fc0: 00000000 00000000 00000000 0000017b 00000000 00000000 00000001 005bc668
>> 7fe0: be907b00 be907af0 b6ce66b0 b6c3fac0 60000010 00000004 00000000 00000000
>> [<c0081bbc>] (frob_text.constprop.16) from [<c0083c4c>]
>> (load_module+0x1888/0x21b4)
>> [<c0083c4c>] (load_module) from [<c00847b0>] (sys_finit_module+0xbc/0xdc)
>> [<c00847b0>] (sys_finit_module) from [<c0009000>] (ret_fast_syscall+0x0/0x50)
>> Exception stack(0xc6837fa8 to 0xc6837ff0)
>> 7fa0: 00000000 00000000 00000004 b6cee714 00000000 00000000
>> 7fc0: 00000000 00000000 00000000 0000017b 00000000 00000000 00000001 005bc668
>> 7fe0: be907b00 be907af0 b6ce66b0 b6c3fac0
>> Code: e1a01621 e1a00002 eafe4531 e7f001f2 (e7f001f2)
>> ---[ end trace 2cbefb0005882c52 ]---
>> Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
>> ---[ end Kernel panic - not syncing: Attempted to kill init!
>> exitcode=0x0000000b ]---
>>
>> I bisected it to commit 06bd260e836d ("modules: fix BUG when load
>> module with rodata=n") with commit 7dabaa5ce05a ("modules: fix compile
>> error if don't have strict module rwx") on top to make it build.
>>
>> Let me know if you need me to provide more info.
>>
>> Best regards,
>> Bartosz Golaszewski
>
> Hi Bartosz,
>
> Thanks for reporting this, I was able to reproduce this on qemu.
>
> This is due to hitting the BUG_ON() in frob_text() due to layout->base
> and/or layout->text_size not being page-aligned. These values are
> always page-aligned when CONFIG_STRICT_MODULE_RWX=y, but in commit
> 2eef1399a86 ("modules: fix BUG when load module with rodata=n"), the
> frob_text()+set_memory_x() calls got moved *outside* of the
> STRICT_MODULE_RWX block since some arches (like x86 and arm64)
> allocate non-executable module memory via module_alloc(), so naturally
> the module text needed to be made executable at a later stage of
> load_module(), regardless of whether STRICT_MODULE_RWX is set or not.
> In your case, you must've had CONFIG_STRICT_MODULE_RWX=n and so we
> were calling frob_text() with non-page-aligned values, triggering the
> BUG_ON().
>
> In any case, could you please try and see if the following patch fixes
> the issue for you?
>
> diff --git a/kernel/module.c b/kernel/module.c
> index 5933395af9a0..cd8df516666d 100644
> --- a/kernel/module.c
> +++ b/kernel/module.c
> @@ -64,14 +64,9 @@
>
> /*
> * Modules' sections will be aligned on page boundaries
> - * to ensure complete separation of code and data, but
> - * only when CONFIG_STRICT_MODULE_RWX=y
> + * to ensure complete separation of code and data
> */
> -#ifdef CONFIG_STRICT_MODULE_RWX
> # define debug_align(X) ALIGN(X, PAGE_SIZE)
> -#else
> -# define debug_align(X) (X)
> -#endif
>
> /* If this is set, the section belongs in the init part of the module */
> #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
Works for me.
Tested-by: David Lechner <[email protected]>
pon., 22 lip 2019 o 18:10 Jessica Yu <[email protected]> napisał(a):
>
> +++ Bartosz Golaszewski [22/07/19 14:12 +0200]:
> >Hi,
> >
> >with v5.3-rc1 I'm hitting the following BUG() when trying to load the
> >gpio-backlight module:
> >
> >kernel BUG at kernel/module.c:1919!
> >Internal error: Oops - BUG: 0 [#1] PREEMPT ARM
> >Modules linked in:
> >CPU: 0 PID: 1 Comm: systemd Tainted: G W
> >5.2.0-rc2-00005-g7dabaa5ce05a #19
> >Hardware name: DaVinci DA850/OMAP-L138/AM18x EVM
> >PC is at frob_text.constprop.16+0x2c/0x34
> >LR is at load_module+0x1888/0x21b4
> >pc : [<c0081bbc>] lr : [<c0083c4c>] psr: 20000013
> >sp : c6837e58 ip : c6b4fa80 fp : bf00574c
> >r10: c0601008 r9 : bf005740 r8 : c0493e38
> >r7 : c00807f8 r6 : 00000000 r5 : 00000001 r4 : c6837f38
> >r3 : 00000fff r2 : bf000000 r1 : 00004b80 r0 : bf005818
> >Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
> >Control: 0005317f Table: c6b78000 DAC: 00000051
> >Process systemd (pid: 1, stack limit = 0x(ptrval))
> >Stack: (0xc6837e58 to 0xc6838000)
> >7e40: bf005740 c6492a90
> >7e60: 00000001 c6bf5788 00000003 c6837f38 bf0058c0 bf0058a8 bf00a495 c0493e38
> >7e80: 00000000 c05368c0 00000001 00000000 c0580030 c0574b28 00000000 00000000
> >7ea0: 00000000 00000000 00000000 00000000 6e72656b 00006c65 00000000 00000000
> >7ec0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> >7ee0: 00000000 00000000 00000000 aefb2bb8 7fffffff c0601008 00000000 00000004
> >7f00: b6cee714 c00091e4 c6836000 00000000 005bc668 c00847b0 7fffffff 00000000
> >7f20: 00000003 00000000 0000b2d0 c884e000 0000b2d0 00000000 c8852dcb c88533a0
> >7f40: c884e000 0000b2d0 c8858cb8 c8858b34 c88568d4 000058c0 00006190 000023b8
> >7f60: 00006713 00000000 00000000 00000000 000023a8 00000024 00000025 00000019
> >7f80: 0000001d 00000011 00000000 aefb2bb8 00000000 00000000 00000000 00000000
> >7fa0: 0000017b c0009000 00000000 00000000 00000004 b6cee714 00000000 00000000
> >7fc0: 00000000 00000000 00000000 0000017b 00000000 00000000 00000001 005bc668
> >7fe0: be907b00 be907af0 b6ce66b0 b6c3fac0 60000010 00000004 00000000 00000000
> >[<c0081bbc>] (frob_text.constprop.16) from [<c0083c4c>]
> >(load_module+0x1888/0x21b4)
> >[<c0083c4c>] (load_module) from [<c00847b0>] (sys_finit_module+0xbc/0xdc)
> >[<c00847b0>] (sys_finit_module) from [<c0009000>] (ret_fast_syscall+0x0/0x50)
> >Exception stack(0xc6837fa8 to 0xc6837ff0)
> >7fa0: 00000000 00000000 00000004 b6cee714 00000000 00000000
> >7fc0: 00000000 00000000 00000000 0000017b 00000000 00000000 00000001 005bc668
> >7fe0: be907b00 be907af0 b6ce66b0 b6c3fac0
> >Code: e1a01621 e1a00002 eafe4531 e7f001f2 (e7f001f2)
> >---[ end trace 2cbefb0005882c52 ]---
> >Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
> >---[ end Kernel panic - not syncing: Attempted to kill init!
> >exitcode=0x0000000b ]---
> >
> >I bisected it to commit 06bd260e836d ("modules: fix BUG when load
> >module with rodata=n") with commit 7dabaa5ce05a ("modules: fix compile
> >error if don't have strict module rwx") on top to make it build.
> >
> >Let me know if you need me to provide more info.
> >
> >Best regards,
> >Bartosz Golaszewski
>
> Hi Bartosz,
>
> Thanks for reporting this, I was able to reproduce this on qemu.
>
> This is due to hitting the BUG_ON() in frob_text() due to layout->base
> and/or layout->text_size not being page-aligned. These values are
> always page-aligned when CONFIG_STRICT_MODULE_RWX=y, but in commit
> 2eef1399a86 ("modules: fix BUG when load module with rodata=n"), the
> frob_text()+set_memory_x() calls got moved *outside* of the
> STRICT_MODULE_RWX block since some arches (like x86 and arm64)
> allocate non-executable module memory via module_alloc(), so naturally
> the module text needed to be made executable at a later stage of
> load_module(), regardless of whether STRICT_MODULE_RWX is set or not.
> In your case, you must've had CONFIG_STRICT_MODULE_RWX=n and so we
> were calling frob_text() with non-page-aligned values, triggering the
> BUG_ON().
>
> In any case, could you please try and see if the following patch fixes
> the issue for you?
>
> diff --git a/kernel/module.c b/kernel/module.c
> index 5933395af9a0..cd8df516666d 100644
> --- a/kernel/module.c
> +++ b/kernel/module.c
> @@ -64,14 +64,9 @@
>
> /*
> * Modules' sections will be aligned on page boundaries
> - * to ensure complete separation of code and data, but
> - * only when CONFIG_STRICT_MODULE_RWX=y
> + * to ensure complete separation of code and data
> */
> -#ifdef CONFIG_STRICT_MODULE_RWX
> # define debug_align(X) ALIGN(X, PAGE_SIZE)
> -#else
> -# define debug_align(X) (X)
> -#endif
>
> /* If this is set, the section belongs in the init part of the module */
> #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
That helps, thanks!
Please Cc me on the actual submitted patch.
Bart