Re: [Qemu-devel] [PATCH] pci: fix bridge IO/BASE

[Blue Swirl]

On Sun, Mar 4, 2012 at 12:21, Michael S. Tsirkin <address@hidden> wrote:
> On Sun, Mar 04, 2012 at 10:27:24AM +0000, Blue Swirl wrote:
>> On Sun, Mar 4, 2012 at 09:46, Michael S. Tsirkin <address@hidden> wrote:
>> > commit 5caef97a16010f818ea8b950e2ee24ba876643ad introduced
>> > a regression: we do not make IO base/limit upper 16
>> > bit registers writeable, so we should report a 16 bit
>> > IO range type, not a 32 bit one.
>> > Note that PCI_PREF_RANGE_TYPE_32 is 0x0, but PCI_IO_RANGE_TYPE_32 is 0x1.
>> >
>> > In particular, this broke sparc64.
>> >
>> > Note: this just reverts to behaviour prior to the patch.
>> > Making PCI_IO_BASE_UPPER16 and PCI_IO_LIMIT_UPPER16
>> > registers writeable should, and seems to, work just as well, but
>> > as no system seems to actually be interested in 32 bit IO,
>> > let's not make unnecessary changes.
>> >
>> > Reported-by: Mark Cave-Ayland <address@hidden>
>> > Signed-off-by: Michael S. Tsirkin <address@hidden>
>> >
>> > Mark, can you confirm that this fixes the bug for you?
>>
>> No, running
>> qemu-system-sparc64 -serial stdio
>> still shows black screen and the following on console:
>> OpenBIOS for Sparc64
>> Unhandled Exception 0x0000000000000032
>> PC = 0x00000000ffd19e18 NPC = 0x00000000ffd19e1c
>> Stopping execution
>
> The weird thing is the range type does not seem to be accessed
> at all. So I guessed there's some memory corruption here.
> Running valgrind shows this:
>
> --11114-- WARNING: unhandled syscall: 340
> --11114-- You may be able to write your own handler.
> --11114-- Read the file README_MISSING_SYSCALL_OR_IOCTL.
> --11114-- Nevertheless we consider this a bug.  Please report
> --11114-- it at http://valgrind.org/support/bug_reports.html.
> ==11114== Invalid read of size 4
> ==11114==    at 0x2A68C0: pci_apb_init (apb_pci.c:350)
> ==11114==    by 0x2F7A84: sun4uv_init (sun4u.c:779)
> ==11114==    by 0x13D716: main (vl.c:3397)
> ==11114==  Address 0x156c7d30 is 0 bytes after a block of size 64
> alloc'd
> ==11114==    at 0x557DD69: malloc (vg_replace_malloc.c:236)
> ==11114==    by 0x225F56: malloc_and_trace (vl.c:2156)
> ==11114==    by 0x584AFEC: ??? (in /lib/libglib-2.0.so.0.2800.8)
> ==11114==    by 0x584B528: g_malloc0 (in /lib/libglib-2.0.so.0.2800.8)
> ==11114==    by 0x19C50C: qemu_allocate_irqs (irq.c:47)
> ==11114==    by 0x2F7A4C: sun4uv_init (sun4u.c:778)
> ==11114==    by 0x13D716: main (vl.c:3397)
> ==11114==
> apb: here
> ==11114== Warning: client switching stacks?  SP change: 0xfec42cbc -->
> 0x16894008
> ==11114==          to suppress, use: --max-stackframe=398791500 or
> greater
> ==11114== Warning: client switching stacks?  SP change: 0x16893fa0 -->
> 0xfec42cc0
> ==11114==          to suppress, use: --max-stackframe=398791392 or
> greater
> ==11114== Warning: client switching stacks?  SP change: 0xfec42fe0 -->
> 0x16893fd0
> ==11114==          to suppress, use: --max-stackframe=398790640 or
> greater
> ==11114==          further instances of this message will not be shown.
> QEMU 1.0.50 monitor - type 'help' for more information
> (qemu) ==11114== Thread 2:
> ==11114== Conditional jump or move depends on uninitialised value(s)
> ==11114==    at 0x2A8351: compute_all_sub (cc_helper.c:37)
> ==11114==    by 0x2A8782: helper_compute_psr (cc_helper.c:470)
> ==11114==    by 0x9AD9A19: ???
> ==11114==
> ==11114== Conditional jump or move depends on uninitialised value(s)
> ==11114==    at 0x2A827C: compute_all_sub_xcc (cc_helper.c:60)
> ==11114==    by 0x2A8795: helper_compute_psr (cc_helper.c:473)
> ==11114==    by 0x9AD9A19: ???
> ==11114==
> ==11114== Conditional jump or move depends on uninitialised value(s)
> ==11114==    at 0x2A8296: compute_all_sub_xcc (cc_helper.c:295)
> ==11114==    by 0x2A8795: helper_compute_psr (cc_helper.c:473)
> ==11114==    by 0x9AD9A19: ???
> ==11114==
>
> Is the above a problem?

It looks like Sparc does not reset registers at CPU reset. Nice catch.

>> This unassigned memory exception is triggered because CMD646 IDE I/O
>> registers are not accessible:
>>
>> (qemu) info pci
>>   Bus  0, device   0, function 0:
>>     Host bridge: PCI device 108e:a000
>>       id ""
>>   Bus  0, device   1, function 0:
>>     PCI bridge: PCI device 108e:5000
>>       BUS 0.
>>       secondary bus 1.
>>       subordinate bus 1.
>>       IO range [0x0000, 0x0fff]
>>       memory range [0x00000000, 0x000fffff]
>>       prefetchable memory range [0x00000000, 0x000fffff]
>>       id ""
>>   Bus  0, device   1, function 1:
>>     PCI bridge: PCI device 108e:5000
>>       BUS 0.
>>       secondary bus 2.
>>       subordinate bus 2.
>>       IO range [0x0000, 0x0fff]
>>       memory range [0x00000000, 0x000fffff]
>>       prefetchable memory range [0x00000000, 0x000fffff]
>>       id ""
>>   Bus  0, device   2, function 0:
>>     VGA controller: PCI device 1234:1111
>>       BAR0: 32 bit prefetchable memory at 0x00800000 [0x00ffffff].
>>       BAR6: 32 bit memory at 0x01000000 [0x0100ffff].
>>       id ""
>>   Bus  0, device   3, function 0:
>>     Bridge: PCI device 108e:1000
>>       BAR0: 32 bit memory at 0x02000000 [0x02ffffff].
>>       BAR1: 32 bit memory at 0x03000000 [0x037fffff].
>>       id ""
>>   Bus  0, device   4, function 0:
>>     Ethernet controller: PCI device 10ec:8029
>>       IRQ 0.
>>       BAR0: I/O at 0xffffffffffffffff [0x00fe].
>>       BAR6: 32 bit memory at 0x03800000 [0x0380ffff].
>>       id ""
>>   Bus  0, device   5, function 0:
>>     IDE controller: PCI device 1095:0646
>>       IRQ 1.
>>       BAR0: I/O at 0xffffffffffffffff [0x0006].
>>       BAR1: I/O at 0xffffffffffffffff [0x0002].
>>       BAR2: I/O at 0xffffffffffffffff [0x0006].
>>       BAR3: I/O at 0xffffffffffffffff [0x0002].
>>       BAR4: I/O at 0xffffffffffffffff [0x000e].
>>       id ""
>> (qemu) info mtree
>> memory
>> 0000000000000000-7ffffffffffffffe (prio 0, RW): system
>>   0000000000000000-0000000007ffffff (prio 0, RW): sun4u.ram
>>   000001fe00000000-000001fe0000ffff (prio 0, RW): apb-config
>>   000001fe01000000-000001fe01ffffff (prio 0, RW): apb-pci-config
>>   000001fe02000000-000001fe0200ffff (prio 0, RW): apb-pci-ioport
>>   000001ff00000000-000001ffffffffff (prio 0, RW): pci-mmio
>>     000001ff00000000-000001ff000fffff (prio 1, RW): alias
>> pci_bridge_mem @pci_bridge_pci 0000000000000000-00000000000fffff
>>     000001ff00000000-000001ff000fffff (prio 1, RW): alias
>> pci_bridge_pref_mem @pci_bridge_pci 0000000000000000-00000000000fffff
>>     000001ff00000000-000001ff000fffff (prio 1, RW): alias
>> pci_bridge_mem @pci_bridge_pci 0000000000000000-00000000000fffff
>>     000001ff00000000-000001ff000fffff (prio 1, RW): alias
>> pci_bridge_pref_mem @pci_bridge_pci 0000000000000000-00000000000fffff
>>     000001ff000a0000-000001ff000affff (prio 2, RW): alias vga.chain4
>> @vga.vram 0000000000000000-000000000000ffff
>>     000001ff000a0000-000001ff000bffff (prio 1, RW): vga-lowmem
>>     000001ff00800000-000001ff00ffffff (prio 1, RW): vga.vram
>>     000001ff01000000-000001ff0100ffff (prio 1, RW): vga.rom
>>     000001ff02000000-000001ff02ffffff (prio 1, RW): isa-mmio
>>     000001ff03000000-000001ff037fffff (prio 1, RW): isa-mmio
>>     000001ff03800000-000001ff0380ffff (prio 1, RW): ne2000.rom
>>   000001fff0000000-000001fff03fffff (prio 0, R-): sun4u.prom
>> pci_bridge_pci
>> 0000000000000000-7ffffffffffffffe (prio 0, RW): pci_bridge_pci
>> pci_bridge_pci
>> 0000000000000000-7ffffffffffffffe (prio 0, RW): pci_bridge_pci
>> vga.vram
>> 0000000000800000-0000000000ffffff (prio 1, RW): vga.vram
>> I/O
>> 0000000000000000-000000000000ffff (prio 0, RW): io
>>   0000000000000000-0000000000000fff (prio 1, RW): alias pci_bridge_io
>> @pci_bridge_io 0000000000000000-0000000000000fff
>>   0000000000000000-0000000000000fff (prio 1, RW): alias pci_bridge_io
>> @pci_bridge_io 0000000000000000-0000000000000fff
>>   0000000000000060-0000000000000060 (prio 0, RW): i8042-data
>>   0000000000000064-0000000000000064 (prio 0, RW): i8042-cmd
>>   0000000000000074-0000000000000077 (prio 0, RW): m48t59
>>   00000000000001ce-00000000000001ce (prio 0, RW): alias vbe @vbe
>> 00000000000001ce-00000000000001ce
>>   00000000000001d0-00000000000001d0 (prio 0, RW): alias vbe @vbe
>> 00000000000001d0-00000000000001d0
>>   0000000000000378-000000000000037f (prio 0, RW): alias parallel
>> @parallel 0000000000000378-000000000000037f
>>   00000000000003b4-00000000000003b5 (prio 0, RW): alias vga @vga
>> 00000000000003b4-00000000000003b5
>>   00000000000003ba-00000000000003ba (prio 0, RW): alias vga @vga
>> 00000000000003ba-00000000000003ba
>>   00000000000003c0-00000000000003cf (prio 0, RW): alias vga @vga
>> 00000000000003c0-00000000000003cf
>>   00000000000003d4-00000000000003d5 (prio 0, RW): alias vga @vga
>> 00000000000003d4-00000000000003d5
>>   00000000000003da-00000000000003da (prio 0, RW): alias vga @vga
>> 00000000000003da-00000000000003da
>>   00000000000003f1-00000000000003f5 (prio 0, RW): alias fdc @fdc
>> 00000000000003f1-00000000000003f5
>>   00000000000003f7-00000000000003f7 (prio 0, RW): alias fdc @fdc
>> 00000000000003f7-00000000000003f7
>>   00000000000003f8-00000000000003ff (prio 0, RW): serial
>>   0000000000000510-0000000000000511 (prio 0, RW): fwcfg
>
> And with type 32 range it looks like this:
>
> 0000000000000000-7ffffffffffffffe (prio 0, RW): system
>  0000000000000000-0000000007ffffff (prio 0, RW): sun4u.ram
>  000001fe00000000-000001fe0000ffff (prio 0, RW): apb-config
>  000001fe01000000-000001fe01ffffff (prio 0, RW): apb-pci-config
>  000001fe02000000-000001fe0200ffff (prio 0, RW): apb-pci-ioport
>  000001ff00000000-000001ffffffffff (prio 0, RW): pci-mmio
>    000001ff00000000-000001ff000fffff (prio 1, RW): alias pci_bridge_mem
> @pci_bridge_pci 0000000000000000-00000000000fffff
>    000001ff00000000-000001ff000fffff (prio 1, RW): alias
> pci_bridge_pref_mem @pci_bridge_pci 0000000000000000-00000000000fffff
>    000001ff00000000-000001ff000fffff (prio 1, RW): alias pci_bridge_mem
> @pci_bridge_pci 0000000000000000-00000000000fffff
>    000001ff00000000-000001ff000fffff (prio 1, RW): alias
> pci_bridge_pref_mem @pci_bridge_pci 0000000000000000-00000000000fffff
>    000001ff000a0000-000001ff000affff (prio 2, RW): alias vga.chain4
> @vga.vram 0000000000000000-000000000000ffff
>    000001ff000a0000-000001ff000bffff (prio 1, RW): vga-lowmem
>    000001ff00800000-000001ff00ffffff (prio 1, RW): vga.vram
>    000001ff01000000-000001ff0100ffff (prio 1, RW): vga.rom
>    000001ff02000000-000001ff02ffffff (prio 1, RW): isa-mmio
>    000001ff03000000-000001ff037fffff (prio 1, RW): isa-mmio
>  000001fff0000000-000001fff03fffff (prio 0, R-): sun4u.prom
> pci_bridge_pci
> 0000000000000000-7ffffffffffffffe (prio 0, RW): pci_bridge_pci
> pci_bridge_pci
> 0000000000000000-7ffffffffffffffe (prio 0, RW): pci_bridge_pci
> vga.vram
> 0000000000800000-0000000000ffffff (prio 1, RW): vga.vram
> I/O
> 0000000000000000-000000000000ffff (prio 0, RW): io
>  0000000000000000-0000000000000fff (prio 1, RW): alias pci_bridge_io
> @pci_bridge_io 0000000000000000-0000000000000fff
>  0000000000000000-0000000000000fff (prio 1, RW): alias pci_bridge_io
> @pci_bridge_io 0000000000000000-0000000000000fff
>  0000000000000060-0000000000000060 (prio 0, RW): i8042-data
>  0000000000000064-0000000000000064 (prio 0, RW): i8042-cmd
>  0000000000000074-0000000000000077 (prio 0, RW): m48t59
>  00000000000001ce-00000000000001ce (prio 0, RW): vbe
>  00000000000001d0-00000000000001d0 (prio 0, RW): vbe
>  0000000000000378-000000000000037f (prio 0, RW): parallel
>  00000000000003b4-00000000000003b5 (prio 0, RW): vga
>  00000000000003ba-00000000000003ba (prio 0, RW): vga
>  00000000000003c0-00000000000003cf (prio 0, RW): vga
>  00000000000003d4-00000000000003d5 (prio 0, RW): vga
>  00000000000003da-00000000000003da (prio 0, RW): vga
>  00000000000003f1-00000000000003f5 (prio 0, RW): fdc
>  00000000000003f7-00000000000003f7 (prio 0, RW): fdc
>  00000000000003f8-00000000000003ff (prio 0, RW): serial
>  0000000000000400-00000000000004ff (prio 1, RW): ne2000
>  0000000000000500-0000000000000507 (prio 1, RW): cmd646-data
>  0000000000000510-0000000000000511 (prio 0, RW): fwcfg
>  0000000000000580-0000000000000583 (prio 1, RW): cmd646-cmd
>  0000000000000600-0000000000000607 (prio 1, RW): cmd646-data
>  0000000000000680-0000000000000683 (prio 1, RW): cmd646-cmd
>  0000000000000700-000000000000070f (prio 1, RW): cmd646-bmdma
>    0000000000000700-0000000000000703 (prio 0, RW): cmd646-bmdma-bus
>    0000000000000704-0000000000000707 (prio 0, RW): cmd646-bmdma-ioport
>    0000000000000708-000000000000070b (prio 0, RW): cmd646-bmdma-bus
>    000000000000070c-000000000000070f (prio 0, RW): cmd646-bmdma-ioport

This looks better.

>
> Sill trying to understand what all this means.
>
>
>> >  hw/pci.c |    4 ++--
>> >  1 files changed, 2 insertions(+), 2 deletions(-)
>> >
>> > diff --git a/hw/pci.c b/hw/pci.c
>> > index fee27fc..6d08cef 100644
>> > --- a/hw/pci.c
>> > +++ b/hw/pci.c
>> > @@ -633,8 +633,8 @@ static void pci_init_mask_bridge(PCIDevice *d)
>> >     memset(d->wmask + PCI_PREF_BASE_UPPER32, 0xff, 8);
>> >
>> >     /* Supported memory and i/o types */
>> > -    d->config[PCI_IO_BASE] |= PCI_IO_RANGE_TYPE_32;
>> > -    d->config[PCI_IO_LIMIT] |= PCI_IO_RANGE_TYPE_32;
>> > +    d->config[PCI_IO_BASE] |= PCI_IO_RANGE_TYPE_16;
>> > +    d->config[PCI_IO_LIMIT] |= PCI_IO_RANGE_TYPE_16;
>> >     pci_word_test_and_set_mask(d->config + PCI_PREF_MEMORY_BASE,
>> >                                PCI_PREF_RANGE_TYPE_64);
>> >     pci_word_test_and_set_mask(d->config + PCI_PREF_MEMORY_LIMIT,
>> > --
>> > 1.7.9.111.gf3fb0