linux_dsm_epyc7002/include
Yinghai Lu aaf2304242 x86: disable the GART early, 64-bit
For K8 system: 4G RAM with memory hole remapping enabled, or more than
4G RAM installed.

when try to use kexec second kernel, and the first doesn't include
gart_shutdown. the second kernel could have different aper position than
the first kernel. and second kernel could use that hole as RAM that is
still used by GART set by the first kernel. esp. when try to kexec
2.6.24 with sparse mem enable from previous kernel (from RHEL 5 or SLES
10). the new kernel will use aper by GART (set by first kernel) for
vmemmap. and after new kernel setting one new GART. the position will be
real RAM. the _mapcount set is lost.

Bad page state in process 'swapper'
page:ffffe2000e600020 flags:0x0000000000000000 mapping:0000000000000000 mapcount:1 count:0
Trying to fix it up, but a reboot is needed
Backtrace:
Pid: 0, comm: swapper Not tainted 2.6.24-rc7-smp-gcdf71a10-dirty #13

Call Trace:
 [<ffffffff8026401f>] bad_page+0x63/0x8d
 [<ffffffff80264169>] __free_pages_ok+0x7c/0x2a5
 [<ffffffff80ba75d1>] free_all_bootmem_core+0xd0/0x198
 [<ffffffff80ba3a42>] numa_free_all_bootmem+0x3b/0x76
 [<ffffffff80ba3461>] mem_init+0x3b/0x152
 [<ffffffff80b959d3>] start_kernel+0x236/0x2c2
 [<ffffffff80b9511a>] _sinittext+0x11a/0x121

and
 [ffffe2000e600000-ffffe2000e7fffff] PMD ->ffff81001c200000 on node 0
phys addr is : 0x1c200000

RHEL 5.1 kernel -53 said:
PCI-DMA: aperture base @ 1c000000 size 65536 KB

new kernel said:
Mapping aperture over 65536 KB of RAM @ 3c000000

So could try to disable that GART if possible.

According to Ingo

> hm, i'm wondering, instead of modifying the GART, why dont we simply
> _detect_ whatever GART settings we have inherited, and propagate that
> into our e820 maps? I.e. if there's inconsistency, then punch that out
> from the memory maps and just dont use that memory.
>
> that way it would not matter whether the GART settings came from a [old
> or crashing] Linux kernel that has not called gart_iommu_shutdown(), or
> whether it's a BIOS that has set up an aperture hole inconsistent with
> the memory map it passed. (or the memory map we _think_ i tried to pass
> us)
>
> it would also be more robust to only read and do a memory map quirk
> based on that, than actively trying to change the GART so early in the
> bootup. Later on we have to re-enable the GART _anyway_ and have to
> punch a hole for it.
>
> and as a bonus, we would have shored up our defenses against crappy
> BIOSes as well.

add e820 modification for gart inconsistent setting.

gart_fix_e820=off could be used to disable e820 fix.

Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:33:09 +01:00
..
acpi x86: dummy placeholder for acpi/reboot.h 2008-01-30 13:31:17 +01:00
asm-alpha
asm-arm ext4: Add ext4_find_next_bit() 2008-01-28 23:58:27 -05:00
asm-avr32 remove __attribute_used__ 2008-01-28 23:21:18 +01:00
asm-blackfin [Blackfin] arch: Add the semtimedop syscall. Upstream uClibc doesn't compile without it. 2008-01-27 19:56:43 +08:00
asm-cris ide: remove stale ide.h "configuration options" 2008-01-25 22:17:08 +01:00
asm-frv ide: remove stale ide.h "configuration options" 2008-01-25 22:17:08 +01:00
asm-generic percpu: make the asm-generic/percpu.h more "generic" 2008-01-30 13:32:52 +01:00
asm-h8300
asm-ia64 percpu: move arch XX_PER_CPU_XX definitions into linux/percpu.h 2008-01-30 13:32:52 +01:00
asm-m32r core: remove last users of empty FASTCALL macro 2008-01-30 13:31:17 +01:00
asm-m68k ext4: Add ext4_find_next_bit() 2008-01-28 23:58:27 -05:00
asm-m68knommu ext4: Add ext4_find_next_bit() 2008-01-28 23:58:27 -05:00
asm-mips [MIPS] Malta, Atlas: move an extern function declaration to the header file 2008-01-29 10:15:05 +00:00
asm-parisc
asm-powerpc percpu: move arch XX_PER_CPU_XX definitions into linux/percpu.h 2008-01-30 13:32:52 +01:00
asm-ppc
asm-s390 percpu: move arch XX_PER_CPU_XX definitions into linux/percpu.h 2008-01-30 13:32:52 +01:00
asm-sh remove __attribute_used__ 2008-01-28 23:21:18 +01:00
asm-sparc
asm-sparc64 percpu: move arch XX_PER_CPU_XX definitions into linux/percpu.h 2008-01-30 13:32:52 +01:00
asm-um git-x86: unbreak UML 2008-01-30 13:32:38 +01:00
asm-v850
asm-x86 x86: disable the GART early, 64-bit 2008-01-30 13:33:09 +01:00
asm-xtensa
crypto [CRYPTO] api: Include sched.h for cond_resched in scatterwalk.h 2008-01-11 08:16:59 +11:00
keys
linux x86: make early printk selectable on 64-bit as well 2008-01-30 13:33:06 +01:00
math-emu
media i2c: Constify client address data 2008-01-27 18:14:46 +01:00
mtd
net [NET_SCHED]: act_api: use PTR_ERR in tcf_action_init/tcf_action_get 2008-01-28 15:11:17 -08:00
pcmcia
rdma RDMA/cma: add support for rdma_migrate_id() 2008-01-25 14:15:32 -08:00
rxrpc
scsi SG: Convert SCSI to use scatterlist helpers for sg chaining 2008-01-28 10:05:27 +01:00
sound
video
xen x86: page.h: make pte_t a union to always include 2008-01-30 13:32:57 +01:00
Kbuild