Re: x86-tip.today (4cdf573) early instaboot
* Mike Galbraith wrote:
> On Tue, 2018-04-10 at 09:06 -0500, Tom Lendacky wrote:
> >
> > Just out of curiosity, can you try the following patch and see if it
> > fixes your reboot issue:
>
> Yup, all better.
>
> > diff --git a/arch/x86/boot/compressed/kaslr.c
> > b/arch/x86/boot/compressed/kaslr.c
> > index c5196d2..a0a50b9 100644
> > --- a/arch/x86/boot/compressed/kaslr.c
> > +++ b/arch/x86/boot/compressed/kaslr.c
> > @@ -55,7 +55,7 @@
> > extern unsigned long get_cmd_line_ptr(void);
> >
> > /* Used by PAGE_KERN* macros: */
> > -pteval_t __default_kernel_pte_mask __read_mostly;
> > +pteval_t __default_kernel_pte_mask __read_mostly = ~0;
> >
> > /* Simplified build-specific string for starting entropy. */
> > static const char build_str[] = UTS_RELEASE " (" LINUX_COMPILE_BY "@"
Thanks guys!
I ended up back-merging this fix (and another fix) into:
fb43d6cb91ef: x86/mm: Do not auto-massage page protections
I added credits as:
- printk format warning fix from: Arnd Bergmann
- boot crash fix from:Tom Lendacky
- crash bisected by: Mike Galbraith
...
Reported-and-fixed-by: Arnd Bergmann
Fixed-by: Tom Lendacky
Bisected-by: Mike Galbraith
Thanks,
Ingo
Re: x86-tip.today (4cdf573) early instaboot
On Tue, 2018-04-10 at 09:06 -0500, Tom Lendacky wrote:
>
> Just out of curiosity, can you try the following patch and see if it
> fixes your reboot issue:
Yup, all better.
> diff --git a/arch/x86/boot/compressed/kaslr.c
> b/arch/x86/boot/compressed/kaslr.c
> index c5196d2..a0a50b9 100644
> --- a/arch/x86/boot/compressed/kaslr.c
> +++ b/arch/x86/boot/compressed/kaslr.c
> @@ -55,7 +55,7 @@
> extern unsigned long get_cmd_line_ptr(void);
>
> /* Used by PAGE_KERN* macros: */
> -pteval_t __default_kernel_pte_mask __read_mostly;
> +pteval_t __default_kernel_pte_mask __read_mostly = ~0;
>
> /* Simplified build-specific string for starting entropy. */
> static const char build_str[] = UTS_RELEASE " (" LINUX_COMPILE_BY "@"
Re: x86-tip.today (4cdf573) early instaboot
On 04/10/2018 07:37 AM, Mike Galbraith wrote:
> On Tue, 2018-04-10 at 10:59 +0200, Ingo Molnar wrote:
>> * Mike Galbraith wrote:
>>
>>> Hi Ingo,
>>>
>>> FYI, my i4790 box reboots immediately.. or close enough to it that you
>>> see nothing at all before again meeting the bios splash. Master with
>>> the ~same config works fine. I haven't poked around yet (work).
>>
>> Hm, so there's been a few 'dangerous' pieces of work merged yesterday-ish.
>>
>> Prime suspects would be:
>>
>> triton:~/tip> gll linus..x86/pti
>>
>> 0564258fb2cf: x86/pti: Leave kernel text global for !PCID
>> a5df4f1f0d78: x86/pti: Never implicitly clear _PAGE_GLOBAL for kernel image
>> e0bb456e3250: x86/pti: Enable global pages for shared areas
>> efad2b415152: x86/mm: Do not forbid _PAGE_RW before init for __ro_after_init
>> 4ddee6efdcd0: x86/mm: Comment _PAGE_GLOBAL mystery
>> e71e836f463d: x86/mm: Remove extra filtering in pageattr code
>> 64c80759408f: x86/mm: Do not auto-massage page protections <== WOOF
>> 6baf4bec02db: x86/espfix: Document use of _PAGE_GLOBAL
>> 8a57f4849f4f: x86/mm: Introduce "default" kernel PTE mask
>> 606c7193d5fb: x86/mm: Undo double _PAGE_PSE clearing
>> d1440b23c922: x86/mm: Factor out pageattr _PAGE_GLOBAL setting
>> ee1400dda318: Merge branch 'linus' into x86/pti to pick up upstream changes
>> 071ccc966ba5: x86/entry/64: Drop idtentry's manual stack switch for user
>> entries
>> 9820e1c3376c: x86/uapi: Fix asm/bootparam.h userspace compilation errors
>>
>> ... which you could test via 0564258fb2cf: if that insta-reboots too then
>> 9820e1c3376c^1 is expected to work and 4 bisection steps should pinpoint the
>> guilty commit ...
>
> Thanks. I already had a full bisect running, so ended up doing more
> than 4 steps, but ended up at the above.
Just out of curiosity, can you try the following patch and see if it
fixes your reboot issue:
diff --git a/arch/x86/boot/compressed/kaslr.c
b/arch/x86/boot/compressed/kaslr.c
index c5196d2..a0a50b9 100644
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -55,7 +55,7 @@
extern unsigned long get_cmd_line_ptr(void);
/* Used by PAGE_KERN* macros: */
-pteval_t __default_kernel_pte_mask __read_mostly;
+pteval_t __default_kernel_pte_mask __read_mostly = ~0;
/* Simplified build-specific string for starting entropy. */
static const char build_str[] = UTS_RELEASE " (" LINUX_COMPILE_BY "@"
Thanks,
Tom
>
> -Mike
>
Re: x86-tip.today (4cdf573) early instaboot
On Tue, 2018-04-10 at 10:59 +0200, Ingo Molnar wrote: > * Mike Galbraith wrote: > > > Hi Ingo, > > > > FYI, my i4790 box reboots immediately.. or close enough to it that you > > see nothing at all before again meeting the bios splash. Master with > > the ~same config works fine. I haven't poked around yet (work). > > Hm, so there's been a few 'dangerous' pieces of work merged yesterday-ish. > > Prime suspects would be: > > triton:~/tip> gll linus..x86/pti > > 0564258fb2cf: x86/pti: Leave kernel text global for !PCID > a5df4f1f0d78: x86/pti: Never implicitly clear _PAGE_GLOBAL for kernel image > e0bb456e3250: x86/pti: Enable global pages for shared areas > efad2b415152: x86/mm: Do not forbid _PAGE_RW before init for __ro_after_init > 4ddee6efdcd0: x86/mm: Comment _PAGE_GLOBAL mystery > e71e836f463d: x86/mm: Remove extra filtering in pageattr code > 64c80759408f: x86/mm: Do not auto-massage page protections <== WOOF > 6baf4bec02db: x86/espfix: Document use of _PAGE_GLOBAL > 8a57f4849f4f: x86/mm: Introduce "default" kernel PTE mask > 606c7193d5fb: x86/mm: Undo double _PAGE_PSE clearing > d1440b23c922: x86/mm: Factor out pageattr _PAGE_GLOBAL setting > ee1400dda318: Merge branch 'linus' into x86/pti to pick up upstream changes > 071ccc966ba5: x86/entry/64: Drop idtentry's manual stack switch for user > entries > 9820e1c3376c: x86/uapi: Fix asm/bootparam.h userspace compilation errors > > ... which you could test via 0564258fb2cf: if that insta-reboots too then > 9820e1c3376c^1 is expected to work and 4 bisection steps should pinpoint the > guilty commit ... Thanks. I already had a full bisect running, so ended up doing more than 4 steps, but ended up at the above. -Mike
Re: x86-tip.today (4cdf573) early instaboot
* Mike Galbraith wrote: > Hi Ingo, > > FYI, my i4790 box reboots immediately.. or close enough to it that you > see nothing at all before again meeting the bios splash. Master with > the ~same config works fine. I haven't poked around yet (work). Hm, so there's been a few 'dangerous' pieces of work merged yesterday-ish. Prime suspects would be: triton:~/tip> gll linus..x86/pti 0564258fb2cf: x86/pti: Leave kernel text global for !PCID a5df4f1f0d78: x86/pti: Never implicitly clear _PAGE_GLOBAL for kernel image e0bb456e3250: x86/pti: Enable global pages for shared areas efad2b415152: x86/mm: Do not forbid _PAGE_RW before init for __ro_after_init 4ddee6efdcd0: x86/mm: Comment _PAGE_GLOBAL mystery e71e836f463d: x86/mm: Remove extra filtering in pageattr code 64c80759408f: x86/mm: Do not auto-massage page protections 6baf4bec02db: x86/espfix: Document use of _PAGE_GLOBAL 8a57f4849f4f: x86/mm: Introduce "default" kernel PTE mask 606c7193d5fb: x86/mm: Undo double _PAGE_PSE clearing d1440b23c922: x86/mm: Factor out pageattr _PAGE_GLOBAL setting ee1400dda318: Merge branch 'linus' into x86/pti to pick up upstream changes 071ccc966ba5: x86/entry/64: Drop idtentry's manual stack switch for user entries 9820e1c3376c: x86/uapi: Fix asm/bootparam.h userspace compilation errors ... which you could test via 0564258fb2cf: if that insta-reboots too then 9820e1c3376c^1 is expected to work and 4 bisection steps should pinpoint the guilty commit ... But there's also the syscall rework: triton:~/tip> gll linus..x86/asm c76fc9826075: syscalls/x86: Adapt syscall_wrapper.h to the new syscall stub naming convention d5a00528b58c: syscalls/core, syscalls/x86: Rename struct pt_regs-based sys_*() to __x64_sys_*() 5ac9efa3c50d: syscalls/core, syscalls/x86: Clean up compat syscall stub naming convention e145242ea0df: syscalls/core, syscalls/x86: Clean up syscall stub naming convention 6dc936f175cc: syscalls/x86: Extend register clearing on syscall entry to lower registers f8781c4a2263: syscalls/x86: Unconditionally enable 'struct pt_regs' based syscalls on x86_64 ebeb8c82ffaf: syscalls/x86: Use 'struct pt_regs' based syscall calling for IA32_EMULATION and x32 7303e30ec1d8: syscalls/core: Prepare CONFIG_ARCH_HAS_SYSCALL_WRAPPER=y for compat syscalls fa697140f9a2: syscalls/x86: Use 'struct pt_regs' based syscall calling convention for 64-bit syscalls 1bd21c6c21e8: syscalls/core: Introduce CONFIG_ARCH_HAS_SYSCALL_WRAPPER=y dfe64506c01e: x86/syscalls: Don't pointlessly reload the system call number ... which you could test via c76fc9826075: if that insta-reboots then dfe64506c01e^1 should be good and 4 bisection steps should suffice. Thanks, Ingo
