RE: [PATCH RFC] x86 early_ioremap: increase FIX_BTMAPS_SLOTS to 8
From: Zheng, Lv
Date: Thu Aug 28 2014 - 02:40:43 EST
Hi,
> From: linux-acpi-owner@xxxxxxxxxxxxxxx [mailto:linux-acpi-owner@xxxxxxxxxxxxxxx] On Behalf Of Dave Young
> Sent: Tuesday, August 26, 2014 5:07 PM
>
> 3.16 kernel boot fail with earlyprintk=efi, it keeps scrolling at the
> bottom line of screen.
>
> Bisected, the first bad commit is below:
> commit 86dfc6f339886559d80ee0d4bd20fe5ee90450f0
> Author: Lv Zheng <lv.zheng@xxxxxxxxx>
> Date: Fri Apr 4 12:38:57 2014 +0800
>
> ACPICA: Tables: Fix table checksums verification before installation.
>
>
> I did some debugging by enabling both serial and efi earlyprintk, below is
> some debug dmesg, seems early_ioremap fails in scroll up function due to
> no free slot, see below dmesg output:
>
> [snip]
> [ 0.000000] RAMDISK: [mem 0x3e1b0000-0x3e982fff]
> [ 0.000000] ACPI: Early table checksum verification disabled
> [ 0.000000] ACPI: RSDP 0x00000000DB752000 000024 (v02 HPQOEM)
> [ 0.000000] ACPI: XSDT 0x00000000DB752088 00008C (v01 HPQOEM SLIC-WKS 01072009 AMI 00010013)
> [ 0.000000] ACPI: FACP 0x00000000DB759590 00010C (v05 HPQOEM SLIC-WKS 01072009 AMI 00010013)
> [ 0.000000] ------------[ cut here ]------------
> [ 0.000000] WARNING: CPU: 0 PID: 0 at mm/early_ioremap.c:116 __early_ioremap+0x90/0x1c4()
> [ 0.000000] __early_ioremap(ed00c800, 00000c80) not found slot
> [ 0.000000] Modules linked in:
> [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 3.17.0-rc1+ #204
> [ 0.000000] Hardware name: Hewlett-Packard HP Z420 Workstation/1589, BIOS J61 v03.15 05/09/2013
> [ 0.000000] 0000000000000000 ffffffff8173b970 ffffffff814bb919 ffffffff8173b9b8
> [ 0.000000] ffffffff8173b9a8 ffffffff810638c9 ffffffff8184ee81 ffffffffff538000
> [ 0.000000] 0000000000000c80 0000000000000003 0000000000000c80 ffffffff8173ba08
> [ 0.000000] Call Trace:
> [ 0.000000] [<ffffffff814bb919>] dump_stack+0x4e/0x7a
> [ 0.000000] [<ffffffff810638c9>] warn_slowpath_common+0x75/0x8e
> [ 0.000000] [<ffffffff8184ee81>] ? __early_ioremap+0x90/0x1c4
> [ 0.000000] [<ffffffff81063929>] warn_slowpath_fmt+0x47/0x49
> [ 0.000000] [<ffffffff8184ee81>] __early_ioremap+0x90/0x1c4
> [ 0.000000] [<ffffffff8124cf4d>] ? sprintf+0x46/0x48
> [ 0.000000] [<ffffffff8184f169>] early_ioremap+0x13/0x15
> [ 0.000000] [<ffffffff814ae4f0>] early_efi_map+0x24/0x26
> [ 0.000000] [<ffffffff81060985>] early_efi_scroll_up+0x6d/0xc0
> [ 0.000000] [<ffffffff81060b88>] early_efi_write+0x1b0/0x214
> [ 0.000000] [<ffffffff8109ec3a>] call_console_drivers.constprop.21+0x73/0x7e
> [ 0.000000] [<ffffffff8109fab4>] console_unlock+0x151/0x3b2
> [ 0.000000] [<ffffffff810a01b4>] ? vprintk_emit+0x49f/0x532
> [ 0.000000] [<ffffffff810a0236>] vprintk_emit+0x521/0x532
> [ 0.000000] [<ffffffff8109fce6>] ? console_unlock+0x383/0x3b2
> [ 0.000000] [<ffffffff814b6f01>] printk+0x4f/0x51
> [ 0.000000] [<ffffffff81292f9c>] acpi_os_vprintf+0x2b/0x2d
> [ 0.000000] [<ffffffff81292fe1>] acpi_os_printf+0x43/0x45
> [ 0.000000] [<ffffffff812bc44c>] acpi_info+0x5c/0x63
> [ 0.000000] [<ffffffff8183cdfa>] ? __acpi_map_table+0x13/0x18
> [ 0.000000] [<ffffffff814afc88>] ? acpi_os_map_iomem+0x21/0x147
> [ 0.000000] [<ffffffff812b7e59>] acpi_tb_print_table_header+0x177/0x186
> [ 0.000000] [<ffffffff812b79da>] acpi_tb_install_table_with_override+0x4b/0x62
> [ 0.000000] [<ffffffff812b7b80>] acpi_tb_install_standard_table+0xd9/0x215
> [ 0.000000] [<ffffffff8184f169>] ? early_ioremap+0x13/0x15
> [ 0.000000] [<ffffffff8183cdfa>] ? __acpi_map_table+0x13/0x18
> [ 0.000000] [<ffffffff81857545>] acpi_tb_parse_root_table+0x16e/0x1b4
> [ 0.000000] [<ffffffff818575e2>] acpi_initialize_tables+0x57/0x59
> [ 0.000000] [<ffffffff8185591d>] acpi_table_init+0x50/0xce
> [ 0.000000] [<ffffffff8183cea2>] acpi_boot_table_init+0x1e/0x85
> [ 0.000000] [<ffffffff81834638>] setup_arch+0x9b7/0xcc4
> [ 0.000000] [<ffffffff81830b3e>] start_kernel+0x94/0x42d
> [ 0.000000] [<ffffffff81830120>] ? early_idt_handlers+0x120/0x120
> [ 0.000000] [<ffffffff818304a2>] x86_64_start_reservations+0x2a/0x2c
> [ 0.000000] [<ffffffff81830597>] x86_64_start_kernel+0xf3/0x100
> [ 0.000000] ---[ end trace 48732c7db414b8fe ]---
> [ 0.000000] ------------[ cut here ]------------
> [ 0.000000] WARNING: CPU: 0 PID: 0 at mm/early_ioremap.c:116 __early_ioremap+0x90/0x1c4()
> [ 0.000000] __early_ioremap(ed00c800, 00000c80) not found slot
> [ 0.000000] Modules linked in:
> [ 0.000000] CPU: 0 PID: 0 Comm: swapper Tainted: G W 3.17.0-rc1+ #204
> [ 0.000000] Hardware name: Hewlett-Packard HP Z420 Workstation/1589, BIOS J61 v03.15 05/09/2013
> [ 0.000000] 0000000000000000 ffffffff8173b970 ffffffff814bb919 ffffffff8173b9b8
> [ 0.000000] ffffffff8173b9a8 ffffffff810638c9 ffffffff8184ee81 ffffffffff538000
> [ 0.000000] 0000000000000c80 0000000000000003 0000000000000c80 ffffffff8173ba08
> [ 0.000000] Call Trace:
> [ 0.000000] [<ffffffff814bb919>] dump_stack+0x4e/0x7a
> [ 0.000000] [<ffffffff810638c9>] warn_slowpath_common+0x75/0x8e
> [ 0.000000] [<ffffffff8184ee81>] ? __early_ioremap+0x90/0x1c4
> [ 0.000000] [<ffffffff81063929>] warn_slowpath_fmt+0x47/0x49
> [ 0.000000] [<ffffffff8184ee81>] __early_ioremap+0x90/0x1c4
> [ 0.000000] [<ffffffff8184f169>] early_ioremap+0x13/0x15
> [ 0.000000] [<ffffffff814ae4f0>] early_efi_map+0x24/0x26
> [ 0.000000] [<ffffffff81060985>] early_efi_scroll_up+0x6d/0xc0
> [ 0.000000] [<ffffffff81060b88>] early_efi_write+0x1b0/0x214
> [ 0.000000] [<ffffffff8109ec3a>] call_console_drivers.constprop.21+0x73/0x7e
> [ 0.000000] [<ffffffff8109fb5d>] console_unlock+0x1fa/0x3b2
> [ 0.000000] [<ffffffff810a0236>] vprintk_emit+0x521/0x532
> [ 0.000000] [<ffffffff8109fce6>] ? console_unlock+0x383/0x3b2
> [ 0.000000] [<ffffffff814b6f01>] printk+0x4f/0x51
> [ 0.000000] [<ffffffff81292f9c>] acpi_os_vprintf+0x2b/0x2d
> [ 0.000000] [<ffffffff81292fe1>] acpi_os_printf+0x43/0x45
> [ 0.000000] [<ffffffff812bc44c>] acpi_info+0x5c/0x63
> [ 0.000000] [<ffffffff8183cdfa>] ? __acpi_map_table+0x13/0x18
> [ 0.000000] [<ffffffff814afc88>] ? acpi_os_map_iomem+0x21/0x147
> [ 0.000000] [<ffffffff812b7e59>] acpi_tb_print_table_header+0x177/0x186
> [ 0.000000] [<ffffffff812b79da>] acpi_tb_install_table_with_override+0x4b/0x62
> [ 0.000000] [<ffffffff812b7b80>] acpi_tb_install_standard_table+0xd9/0x215
> [ 0.000000] [<ffffffff8184f169>] ? early_ioremap+0x13/0x15
> [ 0.000000] [<ffffffff8183cdfa>] ? __acpi_map_table+0x13/0x18
> [ 0.000000] [<ffffffff81857545>] acpi_tb_parse_root_table+0x16e/0x1b4
> [ 0.000000] [<ffffffff818575e2>] acpi_initialize_tables+0x57/0x59
> [ 0.000000] [<ffffffff8185591d>] acpi_table_init+0x50/0xce
> [ 0.000000] [<ffffffff8183cea2>] acpi_boot_table_init+0x1e/0x85
> [ 0.000000] [<ffffffff81834638>] setup_arch+0x9b7/0xcc4
> [ 0.000000] [<ffffffff81830b3e>] start_kernel+0x94/0x42d
> [ 0.000000] [<ffffffff81830120>] ? early_idt_handlers+0x120/0x120
> [ 0.000000] [<ffffffff818304a2>] x86_64_start_reservations+0x2a/0x2c
>
>
> Quote reply from Lv.zheng about the early ioremap slot usage in this case:
>
> """
> In early_efi_scroll_up(), 2 mapping entries will be used for the src/dst screen buffer.
> In drivers/acpi/acpica/tbutils.c, we've improved the early table loading code in acpi_tb_parse_root_table().
> We now need 2 mapping entries:
> 1. One mapping entry is used for RSDT table mapping. Each RSDT entry contains an address for another ACPI table.
> 2. For each entry in RSDP, we need another mapping entry to map the table to perform necessary check/override before installing it.
>
> When acpi_tb_parse_root_table() prints something through EFI earlyprintk console, we'll have 4 mapping entries used.
> The current 4 slots setting of early_ioremap() seems to be too small for such a use case.
> """
In my reply, I only talked about 4 mapping entries which doesn't exceed the current number of early ioremap slot.
Was it better to offer early_ioremap_debug log to prove that we really need to increase it?
And to prove that all of the mappings are done by the code already upstreamed?
Thanks and best regards
-Lv
>
> Thus increase the slot to 8 in this patch to fix this issue.
> boot-time mappings become 512 page with this patch.
>
> Signed-off-by: Dave Young <dyoung@xxxxxxxxxx>
> ---
> I'm not sure if this is ok in 32bit, review and comments are appreciated.
> arch/x86/include/asm/fixmap.h | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> Index: linux/arch/x86/include/asm/fixmap.h
> ===================================================================
> --- linux.orig/arch/x86/include/asm/fixmap.h
> +++ linux/arch/x86/include/asm/fixmap.h
> @@ -106,14 +106,14 @@ enum fixed_addresses {
> __end_of_permanent_fixed_addresses,
>
> /*
> - * 256 temporary boot-time mappings, used by early_ioremap(),
> + * 512 temporary boot-time mappings, used by early_ioremap(),
> * before ioremap() is functional.
> *
> - * If necessary we round it up to the next 256 pages boundary so
> + * If necessary we round it up to the next 512 pages boundary so
> * that we can have a single pgd entry and a single pte table:
> */
> #define NR_FIX_BTMAPS 64
> -#define FIX_BTMAPS_SLOTS 4
> +#define FIX_BTMAPS_SLOTS 8
> #define TOTAL_FIX_BTMAPS (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS)
> FIX_BTMAP_END =
> (__end_of_permanent_fixed_addresses ^
> --
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