The debugtrace entry count is a 32 bit variable, so it can wrap when
lots of trace entries are being produced. Making it wider would result
in a waste of buffer space as the printed count value would consume
more bytes when not wrapping.
So instead of letting the count value grow to huge values let it wrap
and add a wrap counter printed in this situation. This will keep the
needed buffer space at today's value while avoiding to loose a way to
sort all entries in case multiple trace buffers are involved.
Note that the wrap message will be printed before the first trace
entry in case output is switched to console early. This is on purpose
in order to enable a future support of debugtrace to console without
any allocated buffer.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
debugtrace is normally writing trace entries into a single trace
buffer. There are cases where this is not optimal, e.g. when hunting
a bug which requires writing lots of trace entries and one cpu is
stuck. This will result in other cpus filling the trace buffer and
finally overwriting the interesting trace entries of the hanging cpu.
In order to be able to debug such situations add the capability to use
per-cpu trace buffers. This can be selected by specifying the
debugtrace boot parameter with the modifier "cpu:", like:
debugtrace=cpu:16
At the same time switch the parsing function to accept size modifiers
(e.g. 4M or 1G).
Printing out the trace entries is done for each buffer in order to
minimize the effort needed during printing. As each entry is prefixed
with its sequence number sorting the entries can easily be done when
analyzing them.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Report whether shadow paging is supported by the hypervisor, since it
can be disabled at build time.
Reuse and tweak LIBXL_HAVE_PHYSINFO_CAP_HAP as it hasn't appeared in a
released version of Xen yet.
Requested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Current libxl code will always enable Hardware Assisted Paging (HAP),
expecting that the hypervisor will fallback to shadow if HAP is not
available. With the changes to DOMCTL_createdomain that's not the case
any longer, and the hypervisor will raise an error if HAP is not
available instead of silently falling back to shadow.
In order to keep the previous functionality report whether HAP is
available or not in XEN_SYSCTL_physinfo, so that the toolstack can
select a sane default if there's no explicit user selection of whether
HAP should be used.
Note that on ARM hardware HAP capability is always reported since it's
a required feature in order to run Xen.
Fixes: d0c0ba7d3d ('x86/hvm/domain: remove the 'hap_enabled' flag')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <julien.grall@arm.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Commit fd35f32b4b ("tools/x86emul: Use struct cpuid_policy in the
userspace test harnesses") didn't account for the dependencies of
cpuid-autogen.h to potentially change between incremental builds. In
particular the harness has a "run" goal which is supposed to be usable
independently of the rest of the tools sub-tree building, and both the
harness and the fuzzer code are also supposed to be buildable
independently. Therefore a re-build of the generated header needs to be
triggered first, which is achieved by introducing a new top-level target
pattern (for just the "run" part for now).
Further cpuid.o did not have any dependencies added for it.
Finally, while at it, add a "run" target to the cpu-policy test harness.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Since the affinity values are no longer of uniform width, move them
further to the right such that as much of the output as possible comes
out aligned with one another.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
The loop in FOR_EACH_IOREQ_SERVER is backwards hence the cleanup on
failure needs to be done forwards.
Fixes: 97a5a3e301 ('x86/hvm/ioreq: maintain an array of ioreq servers rather than a list')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-28) complains:
xenctrl_stubs.c: In function 'stub_xc_domain_create':
xenctrl_stubs.c:216:28: error: 'val' may be used uninitialized
in this function [-Werror=maybe-uninitialized]
cfg.arch.emulation_flags = ocaml_list_to_c_bitmap
^
xenctrl_stubs.c:198:12: error: 'val' may be used uninitialized
in this function [-Werror=maybe-uninitialized]
cfg.flags = ocaml_list_to_c_bitmap
^
cc1: all warnings being treated as errors
GCC doesn't point at the correct piece of code, but the diagnostic text is
correct, and can occur when the list is empty. Initialise val to 0.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Fix a broken regexp which would mention `$/' when it ought to have
mentioned `$'. The result would be that it would match lines like
type some_ocaml_type = Thing | Other_Thing
but ignore everything but the type name, giving wrong answers.
Check that we check mentioned types. Otherwise if we fail to spot
some suitable thing in the ocaml, we would just omit checking this
type !
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Andrew Cooper <Andrew.Cooper3@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
In the generated C, add some comments saying where we found the ocaml
type. This helps with debugging. (I considered emitting #line
directives but decided this would be more confusing than helpful.)
Improve two dies.
Use better-named filehandles (perl prints thier names when it dies).
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Andrew Cooper <Andrew.Cooper3@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
c/s f089fddd94 broke the Ocaml ABI by renumering
XEN_SYSCTL_PHYSCAP_directio without adjusting the Ocaml
physinfo_cap_flag enumeration.
Add build machinery which will check the ABI correspondence.
This will result in a compile time failure whenever constants get
renumbered/added without a compatible adjustment to the Ocaml ABI.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <Andrew.Cooper3@citrix.com>
c/s f089fddd94 broke the Ocaml ABI by renumering XEN_SYSCTL_PHYSCAP_directio
without adjusting the Ocaml physinfo_cap_flag enumeration. Fix this by
inserting CAP_PV between CAP_HVM and CAP_DirectIO.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Ian Jackson <ian.jackson@eu.citrix.com>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
The code generation for bootsym() is atrocious, and unnecessarily complicated.
Given the appropriate physical address, all we need is to construct a virtual
address of the appropriate type.
add/remove: 0/0 grow/shrink: 0/9 up/down: 0/-4256 (-4256)
Function old new delta
kexec_reserve_area.constprop 165 159 -6
reset_videomode_after_s3 231 70 -161
identify_cpu 1341 1176 -165
parse_acpi_sleep 408 240 -168
early_init_intel 632 440 -192
__cpu_up 1983 1682 -301
do_platform_op 6469 5526 -943
compat_platform_op 6433 5482 -951
__start_xen 12939 11570 -1369
Total: Before=3341298, After=3337042, chg -0.13%
No functional change.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
GCC of a CentOS 6 vintage complains:
cpuid.c: In function 'parse_xen_cpuid':
cpuid.c:32: error: 'mid' may be used uninitialized in this function
This can't occur in practice because the while() loop is guarenteed to be
entered, but initialise mid to work around the issues.
Spotted by Gitlab CI.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
7a0 is an integer field, not a mask - taking the logical and of the hardware
and policy values results in nonsense. Instead, take the policy value
directly.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Roger Pau Monné <roger.pau@cirtrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
As a preparation for per-cpu buffers do a little refactoring of the
debugtrace data: put the needed buffer admin data into the buffer as
it will be needed for each buffer. In order not to limit buffer size
switch the related fields from unsigned int to unsigned long, as on
huge machines with RAM in the TB range it might be interesting to
support buffers >4GB.
While at it switch debugtrace_send_to_console and debugtrace_used to
bool and delete an empty line.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Instead of living in drivers/char/console.c move the debugtrace
related coding to a new file common/debugtrace.c
No functional change, code movement only.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
After dumping the debugtrace buffer it is cleared. This results in some
entries not being printed in case the buffer is dumped again before
having wrapped.
While at it remove the trailing zero byte in the buffer as it is no
longer needed. Commit b5e6e1ee8d introduced passing the number of
chars to be printed in the related interfaces, so the trailing 0 byte
is no longer required.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Current physcaps in XEN_SYSCTL_physinfo are only used by x86, albeit
the capabilities themselves are not x86 specific.
This patch adds support for also reporting the current capabilities on
Arm hardware. Note that on Arm PHYSCAP_hvm is always reported, and
setting PHYSCAP_directio has been moved to common code since the same
logic to set it is used by x86 and Arm.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <julien.grall@arm.com>
setup_fixmap() will setup the fixmap in the boot page tables in order to
use earlyprintk and also update the register r11 holding the address to
the UART.
However, secondary CPUs are not using earlyprintk between turning the
MMU on and switching to the runtime page table. So setting up the
fixmap in the boot pages table is pointless.
This means most of setup_fixmap() is not necessary for the secondary
CPUs. The update of UART address is now moved out of setup_fixmap() and
duplicated in the CPU boot and secondary CPUs boot. Additionally, the
call to setup_fixmap() is removed from secondary CPUs boot.
Lastly, take the opportunity to replace load from literal pool with the
new macro mov_w.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
The assembly switch to the runtime PT is only necessary for the
secondary CPUs. So move the code in the secondary CPUs path.
While this is definitely not compliant with the Arm Arm as we are
switching between two differents set of page-tables without turning off
the MMU. Turning off the MMU is impossible here as the ID map may clash
with other mappings in the runtime page-tables. This will require more
rework to avoid the problem. So for now add a TODO in the code.
Finally, the code is currently assume that r5 will be properly set to 0
before hand. This is done by create_page_tables() which is called quite
early in the boot process. There are a risk this may be oversight in the
future and therefore breaking secondary CPUs boot. Instead, set r5 to 0
just before using it.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Document the behavior and the main registers usage within enable_mmu().
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Document the behavior and the main registers usage within the function.
Note that r6 is now only used within the function, so it does not need
to be part of the common register.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
On secondary CPUs, zero_bss() will be a NOP because BSS only need to be
zeroed once at boot. So the call in the secondary CPUs path can be
removed.
Lastly, document the behavior and the main registers usage within the
function.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
A branch in the success case can be avoided by inverting the branch
condition. At the same time, remove a pointless comment as Xen can only
run at Hypervisor Mode.
Lastly, document the behavior and the main registers usage within the
function.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
The boot code is currently quite difficult to go through because of the
lack of documentation and a number of indirection to avoid executing
some path in either the boot CPU or secondary CPUs.
In an attempt to make the boot code easier to follow, each parts of the
boot are now in separate functions. Furthermore, the paths for the boot
CPU and secondary CPUs are now distinct and for now will call each
functions.
Follow-ups will remove unnecessary calls and do further improvement
(such as adding documentation and reshuffling).
Note that the switch from using the ID mapping to the runtime mapping
is duplicated for each path. This is because in the future we will need
to stay longer in the ID mapping for the boot CPU.
Lastly, it is now required to save lr in cpu_init() becauswe the
function will call other functions and therefore clobber lr.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
At the moment, the user should save r14/lr if it cares about it.
Follow-up patches will introduce more use of putn in place where lr
should be preserved.
Furthermore, any user of putn should also move the value to register r0
if it was stored in a different register.
For convenience, a new macro is introduced to print a given register.
The macro will take care for us to move the value to r0 and also
preserve lr.
Lastly the new macro is used to replace all the callsite of putn. This
will simplify rework/review later on.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Anything executed after the label common_start can be executed on all
CPUs. However most of the instructions executed between the label
common_start and init_uart are not executed on the boot CPU.
The only instructions executed are to lookup the CPUID so it can be
printed on the console (if earlyprintk is enabled). Printing the CPUID
is not entirely useful to have for the boot CPU and requires a
conditional branch to bypass unused instructions.
Furthermore, the function init_uart is only called for boot CPU
requiring another conditional branch. This makes the code a bit tricky
to follow.
The UART initialization is now moved before the label common_start. This
now requires to have a slightly altered print for the boot CPU and set
the early UART base address in each the two path (boot CPU and
secondary CPUs).
This has the nice effect to remove a couple of conditional branch in
the code.
After this rework, the CPUID is only used at the very beginning of the
secondary CPUs boot path. So there is no need to "reserve" x24 for the
CPUID.
Lastly, take the opportunity to replace load from literal pool with the
new macro mov_w.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
The current implementation of the macro PRINT will clobber r14/lr. This
means the user should save r14 if it cares about it.
Follow-up patches will introduce more use of PRINT in places where lr
should be preserved. Rather than requiring all the user to preserve lr,
the macro PRINT is modified to save and restore it.
While the comment state r3 will be clobbered, this is not the case. So
PRINT will use r3 to preserve lr.
Lastly, take the opportunity to move the comment on top of PRINT and use
PRINT in init_uart. Both changes will be helpful in a follow-up patch.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
putn() and puts() are two subroutines. Add ENDPROC for the benefits of
static analysis tools and the reader.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
The current boot code is using the pattern ldr rX, =... to move an
immediate constant into a 32-bit register.
This pattern implies to load the immediate constant from a literal pool,
meaning a memory access will be performed.
The memory access can be avoided by using movw/movt instructions.
A new macro is introduced to move an immediate constant into a 32-bit
register without a memory load. Follow-up patches will make use of it.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
Arm64 provides instructions to load a PC-relative address, but with some
limitations:
- adr is enable to cope with +/-1MB
- adrp is enale to cope with +/-4GB but relative to a 4KB page
address
Because of that, the code requires to use 2 instructions to load any Xen
symbol. To make the code more obvious, introducing a new macro adr_l is
introduced.
The new macro is used to replace a couple of open-coded use in
efi_xen_start.
The macro is copied from Linux 5.2-rc4.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
At the moment, TTBR_EL2 is setup in create_page_tables(). This is fine
as it is called by every CPUs.
However, such assumption may not hold in the future. To make change
easier, the TTBR_EL2 is not setup in enable_mmu().
Take the opportunity to add the missing isb() to ensure the TTBR_EL2 is
seen before the MMU is turned on.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Boot CPU and secondary CPUs will use different entry point to C code. At
the moment, the decision on which entry to use is taken within launch().
In order to avoid a branch for the decision and make the code clearer,
launch() is reworked to take in parameters the entry point and its
arguments.
Lastly, document the behavior and the main registers usage within the
function.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
A follow-up patch will require to use *_table_offset() and *_MASK helpers
from assembly. This can be achieved by using _AT() macro to remove the type
when called from assembly.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
For gen-cpuid.py, fix a comment describing self.names, and generate the
reverse mapping in self.values. Write out INIT_FEATURE_NAMES which maps a
string name to a bit position.
For parse_cpuid(), use cmdline_strcmp() and perform a binary search over
INIT_FEATURE_NAMES. A tweak to cmdline_strcmp() is needed to break at equals
signs as well.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Legacy apic init uses bigsmp for smp systems with 8 and more CPUs. The
bigsmp APIC implementation uses physical destination mode, but it
nevertheless initializes LDR and DFR. The LDR even ends up incorrectly with
multiple bit being set.
This does not cause a functional problem because LDR and DFR are ignored
when physical destination mode is active, but it triggered a problem on a
32-bit KVM guest which jumps into a kdump kernel.
The multiple bits set unearthed a bug in the KVM APIC implementation. The
code which creates the logical destination map for VCPUs ignores the
disabled state of the APIC and ends up overwriting an existing valid entry
and as a result, APIC calibration hangs in the guest during kdump
initialization.
Remove the bogus LDR/DFR initialization.
This is not intended to work around the KVM APIC bug. The LDR/DFR
ininitalization is wrong on its own.
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Bandan Das <bsd@redhat.com>
[Linux commit bae3a8d3308ee69a7dbdf145911b18dfda8ade0d]
Drop init_apic_ldr_x2apic_phys() at the same time.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Although APIC initialization will typically clear out the LDR before
setting it, the APIC cleanup code should reset the LDR.
This was discovered with a 32-bit KVM guest jumping into a kdump
kernel. The stale bits in the LDR triggered a bug in the KVM APIC
implementation which caused the destination mapping for VCPUs to be
corrupted.
Note that this isn't intended to paper over the KVM APIC bug. The kernel
has to clear the LDR when resetting the APIC registers except when X2APIC
is enabled.
Signed-off-by: Bandan Das <bsd@redhat.com>
[Linux commit 558682b5291937a70748d36fd9ba757fb25b99ae]
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Juergen Gross