linux/include/xen/arm/page.h
Masami Hiramatsu 5a0677110b arm/arm64: xen: Fix to convert percpu address to gfn correctly
Use per_cpu_ptr_to_phys() instead of virt_to_phys() for per-cpu
address conversion.

In xen_starting_cpu(), per-cpu xen_vcpu_info address is converted
to gfn by virt_to_gfn() macro. However, since the virt_to_gfn(v)
assumes the given virtual address is in linear mapped kernel memory
area, it can not convert the per-cpu memory if it is allocated on
vmalloc area.

This depends on CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK.
If it is enabled, the first chunk of percpu memory is linear mapped.
In the other case, that is allocated from vmalloc area. Moreover,
if the first chunk of percpu has run out until allocating
xen_vcpu_info, it will be allocated on the 2nd chunk, which is
based on kernel memory or vmalloc memory (depends on
CONFIG_NEED_PER_CPU_KM).

Without this fix and kernel configured to use vmalloc area for
the percpu memory, the Dom0 kernel will fail to boot with following
errors.

[    0.466172] Xen: initializing cpu0
[    0.469601] ------------[ cut here ]------------
[    0.474295] WARNING: CPU: 0 PID: 1 at arch/arm64/xen/../../arm/xen/enlighten.c:153 xen_starting_cpu+0x160/0x180
[    0.484435] Modules linked in:
[    0.487565] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.9.0-rc4+ #4
[    0.493895] Hardware name: Socionext Developer Box (DT)
[    0.499194] pstate: 00000005 (nzcv daif -PAN -UAO BTYPE=--)
[    0.504836] pc : xen_starting_cpu+0x160/0x180
[    0.509263] lr : xen_starting_cpu+0xb0/0x180
[    0.513599] sp : ffff8000116cbb60
[    0.516984] x29: ffff8000116cbb60 x28: ffff80000abec000
[    0.522366] x27: 0000000000000000 x26: 0000000000000000
[    0.527754] x25: ffff80001156c000 x24: fffffdffbfcdb600
[    0.533129] x23: 0000000000000000 x22: 0000000000000000
[    0.538511] x21: ffff8000113a99c8 x20: ffff800010fe4f68
[    0.543892] x19: ffff8000113a9988 x18: 0000000000000010
[    0.549274] x17: 0000000094fe0f81 x16: 00000000deadbeef
[    0.554655] x15: ffffffffffffffff x14: 0720072007200720
[    0.560037] x13: 0720072007200720 x12: 0720072007200720
[    0.565418] x11: 0720072007200720 x10: 0720072007200720
[    0.570801] x9 : ffff8000100fbdc0 x8 : ffff800010715208
[    0.576182] x7 : 0000000000000054 x6 : ffff00001b790f00
[    0.581564] x5 : ffff800010bbf880 x4 : 0000000000000000
[    0.586945] x3 : 0000000000000000 x2 : ffff80000abec000
[    0.592327] x1 : 000000000000002f x0 : 0000800000000000
[    0.597716] Call trace:
[    0.600232]  xen_starting_cpu+0x160/0x180
[    0.604309]  cpuhp_invoke_callback+0xac/0x640
[    0.608736]  cpuhp_issue_call+0xf4/0x150
[    0.612728]  __cpuhp_setup_state_cpuslocked+0x128/0x2c8
[    0.618030]  __cpuhp_setup_state+0x84/0xf8
[    0.622192]  xen_guest_init+0x324/0x364
[    0.626097]  do_one_initcall+0x54/0x250
[    0.630003]  kernel_init_freeable+0x12c/0x2c8
[    0.634428]  kernel_init+0x1c/0x128
[    0.637988]  ret_from_fork+0x10/0x18
[    0.641635] ---[ end trace d95b5309a33f8b27 ]---
[    0.646337] ------------[ cut here ]------------
[    0.651005] kernel BUG at arch/arm64/xen/../../arm/xen/enlighten.c:158!
[    0.657697] Internal error: Oops - BUG: 0 [#1] SMP
[    0.662548] Modules linked in:
[    0.665676] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G        W         5.9.0-rc4+ #4
[    0.673398] Hardware name: Socionext Developer Box (DT)
[    0.678695] pstate: 00000005 (nzcv daif -PAN -UAO BTYPE=--)
[    0.684338] pc : xen_starting_cpu+0x178/0x180
[    0.688765] lr : xen_starting_cpu+0x144/0x180
[    0.693188] sp : ffff8000116cbb60
[    0.696573] x29: ffff8000116cbb60 x28: ffff80000abec000
[    0.701955] x27: 0000000000000000 x26: 0000000000000000
[    0.707344] x25: ffff80001156c000 x24: fffffdffbfcdb600
[    0.712718] x23: 0000000000000000 x22: 0000000000000000
[    0.718107] x21: ffff8000113a99c8 x20: ffff800010fe4f68
[    0.723481] x19: ffff8000113a9988 x18: 0000000000000010
[    0.728863] x17: 0000000094fe0f81 x16: 00000000deadbeef
[    0.734245] x15: ffffffffffffffff x14: 0720072007200720
[    0.739626] x13: 0720072007200720 x12: 0720072007200720
[    0.745008] x11: 0720072007200720 x10: 0720072007200720
[    0.750390] x9 : ffff8000100fbdc0 x8 : ffff800010715208
[    0.755771] x7 : 0000000000000054 x6 : ffff00001b790f00
[    0.761153] x5 : ffff800010bbf880 x4 : 0000000000000000
[    0.766534] x3 : 0000000000000000 x2 : 00000000deadbeef
[    0.771916] x1 : 00000000deadbeef x0 : ffffffffffffffea
[    0.777304] Call trace:
[    0.779819]  xen_starting_cpu+0x178/0x180
[    0.783898]  cpuhp_invoke_callback+0xac/0x640
[    0.788325]  cpuhp_issue_call+0xf4/0x150
[    0.792317]  __cpuhp_setup_state_cpuslocked+0x128/0x2c8
[    0.797619]  __cpuhp_setup_state+0x84/0xf8
[    0.801779]  xen_guest_init+0x324/0x364
[    0.805683]  do_one_initcall+0x54/0x250
[    0.809590]  kernel_init_freeable+0x12c/0x2c8
[    0.814016]  kernel_init+0x1c/0x128
[    0.817583]  ret_from_fork+0x10/0x18
[    0.821226] Code: d0006980 f9427c00 cb000300 17ffffea (d4210000)
[    0.827415] ---[ end trace d95b5309a33f8b28 ]---
[    0.832076] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
[    0.839815] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b ]---

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Link: https://lore.kernel.org/r/160196697165.60224.17470743378683334995.stgit@devnote2
Signed-off-by: Juergen Gross <jgross@suse.com>
2020-10-07 07:08:43 +02:00

121 lines
3.2 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_ARM_XEN_PAGE_H
#define _ASM_ARM_XEN_PAGE_H
#include <asm/page.h>
#include <linux/pfn.h>
#include <linux/types.h>
#include <linux/dma-mapping.h>
#include <linux/pgtable.h>
#include <xen/xen.h>
#include <xen/interface/grant_table.h>
#define phys_to_machine_mapping_valid(pfn) (1)
/* Xen machine address */
typedef struct xmaddr {
phys_addr_t maddr;
} xmaddr_t;
/* Xen pseudo-physical address */
typedef struct xpaddr {
phys_addr_t paddr;
} xpaddr_t;
#define XMADDR(x) ((xmaddr_t) { .maddr = (x) })
#define XPADDR(x) ((xpaddr_t) { .paddr = (x) })
#define INVALID_P2M_ENTRY (~0UL)
/*
* The pseudo-physical frame (pfn) used in all the helpers is always based
* on Xen page granularity (i.e 4KB).
*
* A Linux page may be split across multiple non-contiguous Xen page so we
* have to keep track with frame based on 4KB page granularity.
*
* PV drivers should never make a direct usage of those helpers (particularly
* pfn_to_gfn and gfn_to_pfn).
*/
unsigned long __pfn_to_mfn(unsigned long pfn);
extern struct rb_root phys_to_mach;
/* Pseudo-physical <-> Guest conversion */
static inline unsigned long pfn_to_gfn(unsigned long pfn)
{
return pfn;
}
static inline unsigned long gfn_to_pfn(unsigned long gfn)
{
return gfn;
}
/* Pseudo-physical <-> BUS conversion */
static inline unsigned long pfn_to_bfn(unsigned long pfn)
{
unsigned long mfn;
if (phys_to_mach.rb_node != NULL) {
mfn = __pfn_to_mfn(pfn);
if (mfn != INVALID_P2M_ENTRY)
return mfn;
}
return pfn;
}
static inline unsigned long bfn_to_pfn(unsigned long bfn)
{
return bfn;
}
#define bfn_to_local_pfn(bfn) bfn_to_pfn(bfn)
/* VIRT <-> GUEST conversion */
#define virt_to_gfn(v) \
({ \
WARN_ON_ONCE(!virt_addr_valid(v)); \
pfn_to_gfn(virt_to_phys(v) >> XEN_PAGE_SHIFT); \
})
#define gfn_to_virt(m) (__va(gfn_to_pfn(m) << XEN_PAGE_SHIFT))
#define percpu_to_gfn(v) \
(pfn_to_gfn(per_cpu_ptr_to_phys(v) >> XEN_PAGE_SHIFT))
/* Only used in PV code. But ARM guests are always HVM. */
static inline xmaddr_t arbitrary_virt_to_machine(void *vaddr)
{
BUG();
}
extern int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops,
struct gnttab_map_grant_ref *kmap_ops,
struct page **pages, unsigned int count);
extern int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops,
struct gnttab_unmap_grant_ref *kunmap_ops,
struct page **pages, unsigned int count);
bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn);
bool __set_phys_to_machine_multi(unsigned long pfn, unsigned long mfn,
unsigned long nr_pages);
static inline bool set_phys_to_machine(unsigned long pfn, unsigned long mfn)
{
return __set_phys_to_machine(pfn, mfn);
}
#define xen_remap(cookie, size) ioremap_cache((cookie), (size))
#define xen_unmap(cookie) iounmap((cookie))
bool xen_arch_need_swiotlb(struct device *dev,
phys_addr_t phys,
dma_addr_t dev_addr);
unsigned long xen_get_swiotlb_free_pages(unsigned int order);
#endif /* _ASM_ARM_XEN_PAGE_H */