On Thu, Jun 30, 2016 at 03:17:20PM +0200, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <[email protected]>
>
> Logan Gunthorpe reports that hibernation stopped working reliably for
> him after commit ab76f7b4ab23 (x86/mm: Set NX on gap between __ex_table
> and rodata).
...
> +static int relocate_restore_code(void)
> +{
> + pgd_t *pgd;
> + pud_t *pud;
> +
> + relocated_restore_code = get_safe_page(GFP_ATOMIC);
> + if (!relocated_restore_code)
> + return -ENOMEM;
> +
> + memcpy((void *)relocated_restore_code, &core_restore_code, PAGE_SIZE);
> +
> + /* Make the page containing the relocated code executable */
> + pgd = (pgd_t *)__va(read_cr3()) + pgd_index(relocated_restore_code);
> + pud = pud_offset(pgd, relocated_restore_code);
> + if (pud_large(*pud)) {
> + set_pud(pud, __pud(pud_val(*pud) & ~_PAGE_NX));
> + } else {
> + pmd_t *pmd = pmd_offset(pud, relocated_restore_code);
> +
> + if (pmd_large(*pmd)) {
> + set_pmd(pmd, __pmd(pmd_val(*pmd) & ~_PAGE_NX));
> + } else {
> + pte_t *pte = pte_offset_kernel(pmd,
> relocated_restore_code);
> +
> + set_pte(pte, __pte(pte_val(*pte) & ~_PAGE_NX));
> + }
> + }
> + flush_tlb_all();
I know you want to flush TLBs but this causes the splat below on the
resume kernel.
Most likely because:
resume_target_kernel() does local_irq_disable() and then
swsusp_arch_resume() -> relocate_restore_code() -> flush_tlb_all()
and smp_call_function_many() doesn't like it when IRQs are disabled.
[ 7.613645] Disabling non-boot CPUs ...
[ 7.902408] ------------[ cut here ]------------
[ 7.907106] WARNING: CPU: 0 PID: 1 at kernel/smp.c:416
smp_call_function_many+0xb6/0x260
[ 7.915319] Modules linked in:
[ 7.918501] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.7.0-rc5+ #11
[ 7.924931] Hardware name: To be filled by O.E.M. To be filled by
O.E.M./M5A97 EVO R2.0, BIOS 1503 01/16/2013
[ 7.934967] 0000000000000000 ffff88042b957cf8 ffffffff812ac1c3
0000000000000000
[ 7.942664] 0000000000000000 ffff88042b957d38 ffffffff8105435d
000001a02b957d28
[ 7.950369] 0000000000000000 0000000000000000 ffffffff8104d420
0000000000000000
[ 7.958072] Call Trace:
[ 7.960598] [<ffffffff812ac1c3>] dump_stack+0x67/0x94
[ 7.965815] [<ffffffff8105435d>] __warn+0xdd/0x100
[ 7.970771] [<ffffffff8104d420>] ? leave_mm+0xc0/0xc0
[ 7.975981] [<ffffffff8105444d>] warn_slowpath_null+0x1d/0x20
[ 7.981891] [<ffffffff810cb526>] smp_call_function_many+0xb6/0x260
[ 7.988236] [<ffffffff8104d420>] ? leave_mm+0xc0/0xc0
[ 7.993452] [<ffffffff810cb716>] smp_call_function+0x46/0x80
[ 7.999277] [<ffffffff8104d420>] ? leave_mm+0xc0/0xc0
[ 8.004494] [<ffffffff810cb78e>] on_each_cpu+0x3e/0xa0
[ 8.009790] [<ffffffff81098e00>] ? hibernation_restore+0x130/0x130
[ 8.016135] [<ffffffff8104debc>] flush_tlb_all+0x1c/0x20
[ 8.021613] [<ffffffff815bd8d4>] swsusp_arch_resume+0x254/0x2b0
[ 8.027696] [<ffffffff815bd660>] ? restore_processor_state+0x2f0/0x2f0
[ 8.034387] [<ffffffff81098d9d>] hibernation_restore+0xcd/0x130
[ 8.040464] [<ffffffff81112fbd>] software_resume.part.6+0x1f9/0x25b
[ 8.046894] [<ffffffff81098e26>] software_resume+0x26/0x30
[ 8.052545] [<ffffffff81000449>] do_one_initcall+0x59/0x190
[ 8.058282] [<ffffffff81071b3c>] ? parse_args+0x26c/0x3f0
[ 8.063867] [<ffffffff8168b000>] ? _raw_read_unlock_irqrestore+0x30/0x60
[ 8.070730] [<ffffffff81cd5002>] kernel_init_freeable+0x118/0x19e
[ 8.076986] [<ffffffff816851ae>] kernel_init+0xe/0x100
[ 8.082290] [<ffffffff8168b75f>] ret_from_fork+0x1f/0x40
[ 8.087768] [<ffffffff816851a0>] ? rest_init+0x90/0x90
[ 8.093073] ---[ end trace 6361ce069253f25c ]---
--
Regards/Gruss,
Boris.
ECO tip #101: Trim your mails when you reply.
