From 86bbc2c235e500957b213e7e64ce2e0ccb8bc131 Mon Sep 17 00:00:00 2001 From: Ian Campbell Date: Fri, 21 Nov 2008 10:21:33 +0000 Subject: [PATCH] xen: pin correct PGD on suspend Impact: fix Xen guest boot failure commit eefb47f6a1e855653d275cb90592a3587ea93a09 ("xen: use spin_lock_nest_lock when pinning a pagetable") changed xen_pgd_walk to walk over mm->pgd rather than taking pgd as an argument. This breaks xen_mm_(un)pin_all() because it makes init_mm.pgd readonly instead of the pgd we are interested in and therefore the pin subsequently fails. (XEN) mm.c:2280:d15 Bad type (saw 00000000e8000001 != exp 0000000060000000) for mfn bc464 (pfn 21ca7) (XEN) mm.c:2665:d15 Error while pinning mfn bc464 [ 14.586913] 1 multicall(s) failed: cpu 0 [ 14.586926] Pid: 14, comm: kstop/0 Not tainted 2.6.28-rc5-x86_32p-xenU-00172-gee2f6cc #200 [ 14.586940] Call Trace: [ 14.586955] [] ? printk+0x18/0x1e [ 14.586972] [] xen_mc_flush+0x163/0x1d0 [ 14.586986] [] __xen_pgd_pin+0xa1/0x110 [ 14.587000] [] ? stop_cpu+0x0/0xf0 [ 14.587015] [] xen_mm_pin_all+0x4b/0x70 [ 14.587029] [] xen_suspend+0x39/0xe0 [ 14.587042] [] ? stop_cpu+0x0/0xf0 [ 14.587054] [] stop_cpu+0x9d/0xf0 [ 14.587067] [] run_workqueue+0x8d/0x150 [ 14.587080] [] ? _spin_unlock_irqrestore+0x23/0x40 [ 14.587094] [] ? prepare_to_wait+0x3a/0x70 [ 14.587107] [] worker_thread+0x88/0xf0 [ 14.587120] [] ? autoremove_wake_function+0x0/0x50 [ 14.587133] [] ? worker_thread+0x0/0xf0 [ 14.587146] [] kthread+0x3c/0x70 [ 14.587157] [] ? kthread+0x0/0x70 [ 14.587170] [] kernel_thread_helper+0x7/0x10 [ 14.587181] call 1/3: op=14 arg=[c0415000] result=0 [ 14.587192] call 2/3: op=14 arg=[e1ca2000] result=0 [ 14.587204] call 3/3: op=26 arg=[c1808860] result=-22 Signed-off-by: Ian Campbell Acked-by: Jeremy Fitzhardinge Signed-off-by: Ingo Molnar --- arch/x86/xen/mmu.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index 688936044dc9..636ef4caa52d 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -661,12 +661,11 @@ void xen_set_pgd(pgd_t *ptr, pgd_t val) * For 64-bit, we must skip the Xen hole in the middle of the address * space, just after the big x86-64 virtual hole. */ -static int xen_pgd_walk(struct mm_struct *mm, - int (*func)(struct mm_struct *mm, struct page *, - enum pt_level), - unsigned long limit) +static int __xen_pgd_walk(struct mm_struct *mm, pgd_t *pgd, + int (*func)(struct mm_struct *mm, struct page *, + enum pt_level), + unsigned long limit) { - pgd_t *pgd = mm->pgd; int flush = 0; unsigned hole_low, hole_high; unsigned pgdidx_limit, pudidx_limit, pmdidx_limit; @@ -753,6 +752,14 @@ out: return flush; } +static int xen_pgd_walk(struct mm_struct *mm, + int (*func)(struct mm_struct *mm, struct page *, + enum pt_level), + unsigned long limit) +{ + return __xen_pgd_walk(mm, mm->pgd, func, limit); +} + /* If we're using split pte locks, then take the page's lock and return a pointer to it. Otherwise return NULL. */ static spinlock_t *xen_pte_lock(struct page *page, struct mm_struct *mm) @@ -854,7 +861,7 @@ static void __xen_pgd_pin(struct mm_struct *mm, pgd_t *pgd) xen_mc_batch(); - if (xen_pgd_walk(mm, xen_pin_page, USER_LIMIT)) { + if (__xen_pgd_walk(mm, pgd, xen_pin_page, USER_LIMIT)) { /* re-enable interrupts for flushing */ xen_mc_issue(0); @@ -998,7 +1005,7 @@ static void __xen_pgd_unpin(struct mm_struct *mm, pgd_t *pgd) PT_PMD); #endif - xen_pgd_walk(mm, xen_unpin_page, USER_LIMIT); + __xen_pgd_walk(mm, pgd, xen_unpin_page, USER_LIMIT); xen_mc_issue(0); } -- 2.30.2