120845 Commits

Author SHA1 Message Date
Peter Maydell
4de25ed588 target/arm: Handle FPCR.AH in SVE FABS
Make SVE FABS honour the FPCR.AH "don't negate the sign of a NaN"
semantics.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
47d3216240 target/arm: Handle FPCR.AH in SVE FNEG
Make SVE FNEG honour the FPCR.AH "don't negate the sign of a NaN"
semantics.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
538deec623 target/arm: Handle FPCR.AH in vector FABD
Split the handling of vector FABD so that it calls a different set
of helpers when FPCR.AH is 1, which implement the "no negation of
the sign of a NaN" semantics.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
d091ce2d3f target/arm: Implement FPCR.AH handling for scalar FABS and FABD
FPCR.AH == 1 mandates that taking the absolute value of a NaN should
not change its sign bit.  This means we can no longer use
gen_vfp_abs*() everywhere but must instead generate slightly more
complex code when FPCR.AH is set.

Implement these semantics for scalar FABS and FABD.  This change also
affects all other instructions whose psuedocode calls FPAbs(); we
will extend the change to those instructions in following commits.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
e76df44d2d target/arm: Implement FPCR.AH handling of negation of NaN
FPCR.AH == 1 mandates that negation of a NaN value should not flip
its sign bit.  This means we can no longer use gen_vfp_neg*()
everywhere but must instead generate slightly more complex code when
FPCR.AH is set.

Make this change for the scalar FNEG and for those places in
translate-a64.c which were previously directly calling
gen_vfp_neg*().

This change in semantics also affects any other instruction whose
pseudocode calls FPNeg(); in following commits we extend this
change to the other affected instructions.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
4ba5383bc5 target/arm: Implement FPCR.AH semantics for SVE FMIN/FMAX vector
Implement the FPCR.AH semantics for the SVE FMAX and FMIN
operations that take two vector operands.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
bf92725bb2 target/arm: Implement FPCR.AH semantics for SVE FMIN/FMAX immediate
Implement the FPCR.AH semantics for the SVE FMAX and FMIN operations
that take an immediate as the second operand.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
dac3a42f39 target/arm: Implement FPCR.AH semantics for SVE FMAXV and FMINV
Implement the FPCR.AH semantics for the SVE FMAXV and FMINV
vector-reduction-to-scalar max/min operations.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
384433e709 target/arm: Implement FPCR.AH semantics for FMINP and FMAXP
Implement the FPCR.AH semantics for the pairwise floating
point minimum/maximum insns FMINP and FMAXP.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
bb9330b662 target/arm: Implement FPCR.AH semantics for FMAXV and FMINV
Implement the FPCR.AH semantics for FMAXV and FMINV.  These are the
"recursively reduce all lanes of a vector to a scalar result" insns;
we just need to use the _ah_ helper for the reduction step when
FPCR.AH == 1.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
d613e44010 target/arm: Implement FPCR.AH semantics for vector FMIN/FMAX
Implement the FPCR.AH == 1 semantics for vector FMIN/FMAX, by
creating new _ah_ versions of the gvec helpers which invoke the
scalar fmin_ah and fmax_ah helpers on each element.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
2a734f3fe3 target/arm: Implement FPCR.AH semantics for scalar FMIN/FMAX
When FPCR.AH == 1, floating point FMIN and FMAX have some odd special
cases:

 * comparing two zeroes (even of different sign) or comparing a NaN
   with anything always returns the second argument (possibly
   squashed to zero)
 * denormal outputs are not squashed to zero regardless of FZ or FZ16

Implement these semantics in new helper functions and select them at
translate time if FPCR.AH is 1 for the scalar FMAX and FMIN insns.
(We will convert the other FMAX and FMIN insns in subsequent
commits.)

Note that FMINNM and FMAXNM are not affected.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
7bcde0c6dd target/arm: Handle FPCR.NEP for NEP for FMUL, FMULX scalar by element
do_fp3_scalar_idx() is used only for the FMUL and FMULX scalar by
element instructions; these both need to merge the result with the Rn
register when FPCR.NEP is set.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
555639065d target/arm: Handle FPCR.NEP for FCVTXN (scalar)
Unlike the other users of do_2misc_narrow_scalar(), FCVTXN (scalar)
is always double-to-single and must honour FPCR.NEP.  Implement this
directly in a trans function rather than using
do_2misc_narrow_scalar().

We still need gen_fcvtxn_sd() and the f_scalar_fcvtxn[] array for
the FCVTXN (vector) insn, so we move those down in the file to
where they are used.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
64339259a9 target/arm: Handle FPCR.NEP for scalar FABS and FNEG
Handle FPCR.NEP merging for scalar FABS and FNEG; this requires
an extra parameter to do_fp1_scalar_int(), since FMOV scalar
does not have the merging behaviour.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
13ab4eb190 target/arm: Handle FPCR.NEP in do_cvtf_scalar()
Handle FPCR.NEP in the operations handled by do_cvtf_scalar().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
3f88032ce2 target/arm: Handle FPCR.NEP for 1-input scalar operations
Handle FPCR.NEP for the 1-input scalar operations.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
053b39aad9 target/arm: Handle FPCR.NEP for BFCVT scalar
Currently we implement BFCVT scalar via do_fp1_scalar().  This works
even though BFCVT is a narrowing operation from 32 to 16 bits,
because we can use write_fp_sreg() for float16. However, FPCR.NEP
support requires that we use write_fp_hreg_merging() for float16
outputs, so we can't continue to borrow the non-narrowing
do_fp1_scalar() function for this. Split out trans_BFCVT_s()
into its own implementation that honours FPCR.NEP.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
0378199dc2 target/arm: Handle FPCR.NEP for 3-input scalar operations
Handle FPCR.NEP for the 3-input scalar operations which use
do_fmla_scalar_idx() and do_fmadd(), by making them call the
appropriate write_fp_*reg_merging() functions.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
78dcfe20e9 target/arm: Define and use new write_fp_*reg_merging() functions
For FEAT_AFP's FPCR.NEP bit, we need to programmatically change the
behaviour of the writeback of the result for most SIMD scalar
operations, so that instead of zeroing the upper part of the result
register it merges the upper elements from one of the input
registers.

Provide new functions write_fp_*reg_merging() which can be used
instead of the existing write_fp_*reg() functions when we want this
"merge the result with one of the input registers if FPCR.NEP is
enabled" handling, and use them in do_fp3_scalar_with_fpsttype().

Note that (as documented in the description of the FPCR.NEP bit)
which input register to use as the merge source varies by
instruction: for these 2-input scalar operations, the comparison
instructions take from Rm, not Rn.

We'll extend this to also provide the merging behaviour for
the remaining scalar insns in subsequent commits.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
7025fa996f target/arm: Add FPCR.NEP to TBFLAGS
For FEAT_AFP, we want to emit different code when FPCR.NEP is set, so
that instead of zeroing the high elements of a vector register when
we write the output of a scalar operation to it, we instead merge in
those elements from one of the source registers.  Since this affects
the generated code, we need to put FPCR.NEP into the TBFLAGS.

FPCR.NEP is treated as 0 when in streaming SVE mode and FEAT_SME_FA64
is not implemented or not enabled; we can implement this logic in
rebuild_hflags_a64().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
8a5a2b943e target/arm: Use FPST_FPCR_AH for BFMLAL*, BFMLSL* insns
When FPCR.AH is 1, use FPST_FPCR_AH for:
 * AdvSIMD BFMLALB, BFMLALT
 * SVE BFMLALB, BFMLALT, BFMLSLB, BFMLSLT

so that they get the required behaviour changes.

We do this by making gen_gvec_op4_fpst() take an ARMFPStatusFlavour
rather than a bool is_fp16; existing callsites now select
FPST_FPCR_F16_A64 vs FPST_FPCR_A64 themselves rather than passing in
the boolean.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
b6295046e6 target/arm: Use FPST_FPCR_AH for BFCVT* insns
When FPCR.AH is 1, use FPST_FPCR_AH for:
 * AdvSIMD BFCVT, BFCVTN, BFCVTN2
 * SVE BFCVT, BFCVTNT

so that they get the required behaviour changes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
a8559e0e53 target/arm: Use FPST_FPCR_AH for FRECPE, FRECPS, FRECPX, FRSQRTE, FRSQRTS
For the instructions FRECPE, FRECPS, FRECPX, FRSQRTE, FRSQRTS, use
FPST_FPCR_AH or FPST_FPCR_AH_F16 when FPCR.AH is 1, so that they get
the required behaviour changes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
1828053990 target/arm: Set up float_status to use for FPCR.AH=1 behaviour
When FPCR.AH is 1, the behaviour of some instructions changes:
 * AdvSIMD BFCVT, BFCVTN, BFCVTN2, BFMLALB, BFMLALT
 * SVE BFCVT, BFCVTNT, BFMLALB, BFMLALT, BFMLSLB, BFMLSLT
 * SME BFCVT, BFCVTN, BFMLAL, BFMLSL (these are all in SME2 which
   QEMU does not yet implement)
 * FRECPE, FRECPS, FRECPX, FRSQRTE, FRSQRTS

The behaviour change is:
 * the instructions do not update the FPSR cumulative exception flags
 * trapped floating point exceptions are disabled (a no-op for QEMU,
   which doesn't implement FPCR.{IDE,IXE,UFE,OFE,DZE,IOE})
 * rounding is always round-to-nearest-even regardless of FPCR.RMode
 * denormalized inputs and outputs are always flushed to zero, as if
   FPCR.{FZ,FIZ} is {1,1}
 * FPCR.FZ16 is still honoured for half-precision inputs

(See the Arm ARM DDI0487L.a section A1.5.9.)

We can provide all these behaviours with another pair of float_status fields
which we use only for these insns, when FPCR.AH is 1. These float_status
fields will always have:
 * flush_to_zero and flush_inputs_to_zero set for the non-F16 field
 * rounding mode set to round-to-nearest-even
and so the only FPCR fields they need to honour are DN and FZ16.

In this commit we only define the new fp_status fields and give them
the required behaviour when FPSR is updated.  In subsequent commits
we will arrange to use this new fp_status field for the instructions
that should be affected by FPCR.AH in this way.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
731528d35e target/arm: Add FPCR.AH to tbflags
We are going to need to generate different code in some cases when
FPCR.AH is 1.  For example:
 * Floating point neg and abs must not flip the sign bit of NaNs
 * some insns (FRECPE, FRECPS, FRECPX, FRSQRTE, FRSQRTS, and various
   BFCVT and BFM bfloat16 ops) need to use a different float_status
   to the usual one

Encode FPCR.AH into the A64 tbflags, so we can refer to it at
translate time.

Because we now have a bit in FPCR that affects codegen, we can't mark
the AArch64 FPCR register as being SUPPRESS_TB_END any more; writes
to it will now end the TB and trigger a regeneration of hflags.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
a4550b7be9 target/arm: Adjust exception flag handling for AH = 1
When FPCR.AH = 1, some of the cumulative exception flags in the FPSR
behave slightly differently for A64 operations:
 * IDC is set when a denormal input is used without flushing
 * IXC (Inexact) is set when an output denormal is flushed to zero

Update vfp_get_fpsr_from_host() to do this.

Note that because half-precision operations never set IDC, we now
need to add float_flag_input_denormal_used to the set we mask out of
fp_status_f16_a64.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
b3d00d0a44 target/arm: Adjust FP behaviour for FPCR.AH = 1
When FPCR.AH is set, various behaviours of AArch64 floating point
operations which are controlled by softfloat config settings change:
 * tininess and ftz detection before/after rounding
 * NaN propagation order
 * result of 0 * Inf + NaN
 * default NaN value

When the guest changes the value of the AH bit, switch these config
settings on the fp_status_a64 and fp_status_f16_a64 float_status
fields.

This requires us to make the arm_set_default_fp_behaviours() function
global, since we now need to call it from cpu.c and vfp_helper.c; we
move it to vfp_helper.c so it can be next to the new
arm_set_ah_fp_behaviours().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
c2e6020477 target/arm: Implement FPCR.FIZ handling
Part of FEAT_AFP is the new control bit FPCR.FIZ.  This bit affects
flushing of single and double precision denormal inputs to zero for
AArch64 floating point instructions.  (For half-precision, the
existing FPCR.FZ16 control remains the only one.)

FPCR.FIZ differs from FPCR.FZ in that if we flush an input denormal
only because of FPCR.FIZ then we should *not* set the cumulative
exception bit FPSR.IDC.

FEAT_AFP also defines that in AArch64 the existing FPCR.FZ only
applies when FPCR.AH is 0.

We can implement this by setting the "flush inputs to zero" state
appropriately when FPCR is written, and by not reflecting the
float_flag_input_denormal status flag into FPSR reads when it is the
result only of FPSR.FIZ.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
7ea2b119f9 target/arm: Define FPCR AH, FIZ, NEP bits
The Armv8.7 FEAT_AFP feature defines three new control bits in
the FPCR:
 * FPCR.AH: "alternate floating point mode"; this changes floating
   point behaviour in a variety of ways, including:
    - the sign of a default NaN is 1, not 0
    - if FPCR.FZ is also 1, denormals detected after rounding
      with an unbounded exponent has been applied are flushed to zero
    - FPCR.FZ does not cause denormalized inputs to be flushed to zero
    - miscellaneous other corner-case behaviour changes
 * FPCR.FIZ: flush denormalized numbers to zero on input for
   most instructions
 * FPCR.NEP: makes scalar SIMD operations merge the result with
   higher vector elements in one of the source registers, instead
   of zeroing the higher elements of the destination

This commit defines the new bits in the FPCR, and allows them to be
read or written when FEAT_AFP is implemented.  Actual behaviour
changes will be implemented in subsequent commits.

Note that these are the first FPCR bits which don't appear in the
AArch32 FPSCR view of the register, and which share bit positions
with FPSR bits.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
28f13bccbe fpu: allow flushing of output denormals to be after rounding
Currently we handle flushing of output denormals in uncanon_normal
always before we deal with rounding.  This works for architectures
that detect tininess before rounding, but is usually not the right
place when the architecture detects tininess after rounding.  For
example, for x86 the SDM states that the MXCSR FTZ control bit causes
outputs to be flushed to zero "when it detects a floating-point
underflow condition".  This means that we mustn't flush to zero if
the input is such that after rounding it is no longer tiny.

At least one of our guest architectures does underflow detection
after rounding but flushing of denormals before rounding (MIPS MSA);
this means we need to have a config knob for this that is separate
from our existing tininess_before_rounding setting.

Add an ftz_detection flag.  For consistency with
tininess_before_rounding, we make it default to "detect ftz after
rounding"; this means that we need to explicitly set the flag to
"detect ftz before rounding" on every existing architecture that sets
flush_to_zero, so that this commit has no behaviour change.
(This means more code change here but for the long term a less
confusing API.)

For several architectures the current behaviour is either
definitely or possibly wrong; annotate those with TODO comments.
These architectures are definitely wrong (and should detect
ftz after rounding):
 * x86
 * Alpha

For these architectures the spec is unclear:
 * MIPS (for non-MSA)
 * RX
 * SH4

PA-RISC makes ftz detection IMPDEF, but we aren't setting the
"tininess before rounding" setting that we ought to.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
029a2083a2 fpu: Implement float_flag_input_denormal_used
For the x86 and the Arm FEAT_AFP semantics, we need to be able to
tell the target code that the FPU operation has used an input
denormal.  Implement this; when it happens we set the new
float_flag_denormal_input_used.

Note that we only set this when an input denormal is actually used by
the operation: if the operation results in Invalid Operation or
Divide By Zero or the result is a NaN because some other input was a
NaN then we never needed to look at the input denormal and do not set
denormal_input_used.

We mostly do not need to adjust the hardfloat codepaths to deal with
this flag, because almost all hardfloat operations are already gated
on the input not being a denormal, and will fall back to softfloat
for a denormal input.  The only exception is the comparison
operations, where we need to add the check for input denormals, which
must now fall back to softfloat where they did not before.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Peter Maydell
7ad6a56757 fpu: Add float_class_denormal
Currently in softfloat we canonicalize input denormals and so the
code that implements floating point operations does not need to care
whether the input value was originally normal or denormal.  However,
both x86 and Arm FEAT_AFP require that an exception flag is set if:
 * an input is denormal
 * that input is not squashed to zero
 * that input is actually used in the calculation (e.g. we
   did not find the other input was a NaN)

So we need to track that the input was a non-squashed denormal.  To
do this we add a new value to the FloatClass enum.  In this commit we
add the value and adjust the code everywhere that looks at FloatClass
values so that the new float_class_denormal behaves identically to
float_class_normal.  We will add the code that does the "raise a new
float exception flag if an input was an unsquashed denormal and we
used it" in a subsequent commit.

There should be no behavioural change in this commit.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2025-02-11 16:22:07 +00:00
Cédric Le Goater
be7d8579eb vfio: Remove superfluous error report in vfio_listener_region_add()
For pseries machines, commit 567b5b309abe ("vfio/pci: Relax DMA map
errors for MMIO regions") introduced 2 error reports to notify the
user of MMIO mapping errors. Consolidate both code paths under one.

Cc: Harsh Prateek Bora <harshpb@linux.ibm.com>
Cc: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/qemu-devel/20250206131438.1505542-8-clg@redhat.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2025-02-11 14:15:19 +01:00
Cédric Le Goater
889695f8f3 vfio: Remove reports of DMA mapping errors in backends
Currently, the mapping handlers of the IOMMU backends, VFIO IOMMU Type
1 aka. legacy and IOMMUFD, return an errno and also report an error.
This can lead to excessive log messages at runtime for recurring DMA
mapping errors. Since these errors are already reported by the callers
in the vfio_container_dma_un/map() routines, simply remove them and
allow the callers to handle the reporting.

The mapping handler of the IOMMUFD backend has a comment suggesting
MMIO region mapping failures return EFAULT. I am not sure this is
entirely true, so keep the EFAULT case until the conditions are
clarified.

Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/qemu-devel/20250206131438.1505542-7-clg@redhat.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2025-02-11 14:15:19 +01:00
Cédric Le Goater
aaec00422b vfio: Improve error reporting when MMIO region mapping fails
When the IOMMU address space width is smaller than the physical
address width, a MMIO region of a device can fail to map because the
region is outside the supported IOVA ranges of the VM. In this case,
PCI peer-to-peer transactions on BARs are not supported. This can
occur with the 39-bit IOMMU address space width, as can be the case on
some Intel consumer processors, or when using a vIOMMU device with
default settings.

The current error message is unclear, improve it and also change the
error report to a warning because it is a non fatal condition for the
VM. To prevent excessive log messages, restrict these recurring DMA
mapping errors to a single warning at runtime.

Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/qemu-devel/20250206131438.1505542-6-clg@redhat.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2025-02-11 14:15:19 +01:00
Cédric Le Goater
80936cf7f3 vfio: Introduce vfio_get_vfio_device()
This helper will be useful in the listener handlers to extract the
VFIO device from a memory region using memory_region_owner(). At the
moment, we only care for PCI passthrough devices. If the need arises,
we will add more.

Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/qemu-devel/20250206131438.1505542-5-clg@redhat.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2025-02-11 14:15:19 +01:00
Cédric Le Goater
cdc6f2e0c9 vfio: Rephrase comment in vfio_listener_region_add() error path
Rephrase a bit the ending comment about how errors are handled
depending on the phase in which vfio_listener_region_add() is called.

Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/qemu-devel/20250206131438.1505542-4-clg@redhat.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2025-02-11 14:15:19 +01:00
Cédric Le Goater
cbfbedd617 vfio/pci: Replace "iommu_device" by "vIOMMU"
This is to be consistent with other reported errors related to vIOMMU
devices.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/qemu-devel/20250206131438.1505542-3-clg@redhat.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2025-02-11 14:15:19 +01:00
Cédric Le Goater
96b339cc4c util/error: Introduce warn_report_err_once()
Depending on the configuration of the host and VM, a passthrough
device may generate recurring DMA mapping errors at runtime. In such
cases, reporting the issue once is sufficient.

We have already the warn/error_report_once() routines taking a format
and arguments. Using the same design pattern, add a new warning
variant taking an 'Error *' parameter.

Cc: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Link: https://lore.kernel.org/qemu-devel/20250206131438.1505542-2-clg@redhat.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2025-02-11 14:15:19 +01:00
Zhenzhong Duan
7b3d5b84cb vfio/iommufd: Fix SIGSEV in iommufd_cdev_attach()
When iommufd_cdev_ram_block_discard_disable() fails for whatever reason,
errp should be set or else SIGSEV is triggered in vfio_realize() when
error_prepend() is called.

By this chance, use the same error message for both legacy and iommufd
backend.

Fixes: 5ee3dc7af785 ("vfio/iommufd: Implement the iommufd backend")
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/20250116102307.260849-1-zhenzhong.duan@intel.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2025-02-11 14:15:19 +01:00
Tomita Moeko
e45891e0b1 vfio/igd: use VFIOConfigMirrorQuirk for mirrored registers
With the introduction of config_offset field, VFIOConfigMirrorQuirk can
now be used for those mirrored register in igd bar0. This eliminates
the need for the macro intoduced in 1a2623b5c9e7 ("vfio/igd: add macro
for declaring mirrored registers").

Signed-off-by: Tomita Moeko <tomitamoeko@gmail.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/r/20250104154219.7209-4-tomitamoeko@gmail.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2025-02-11 14:15:19 +01:00
Tomita Moeko
f36e7ba975 vfio/pci: introduce config_offset field in VFIOConfigMirrorQuirk
Device may only expose a specific portion of PCI config space through a
region in a BAR, such behavior is seen in igd GGC and BDSM mirrors in
BAR0. To handle these, config_offset is introduced to allow mirroring
arbitrary region in PCI config space.

Signed-off-by: Tomita Moeko <tomitamoeko@gmail.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/r/20250104154219.7209-3-tomitamoeko@gmail.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2025-02-11 14:15:19 +01:00
Tomita Moeko
dee69a8ca6 vfio/pci: declare generic quirks in a new header file
Declare generic vfio_generic_{window_address,window_data,mirror}_quirk
in newly created pci_quirks.h so that they can be used elsewhere, like
igd.c.

Signed-off-by: Tomita Moeko <tomitamoeko@gmail.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/r/20250104154219.7209-2-tomitamoeko@gmail.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2025-02-11 14:15:19 +01:00
Cédric Le Goater
6e7998ceb9 vfio/igd: Fix potential overflow in igd_gtt_memory_size()
The risk is mainly theoretical since the applied bit mask will keep
the 'ggms' shift value below 3. Nevertheless, let's use a 64 bit
integer type and resolve the coverity issue.

Resolves: Coverity CID 1585908
Fixes: 1e1eac5f3dcd ("vfio/igd: canonicalize memory size calculations")
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/r/20250107130604.669697-1-clg@redhat.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2025-02-11 14:15:19 +01:00
Peter Maydell
f0c29a0234 target/alpha: Don't corrupt error_code with unknown softfloat flags
In do_cvttq() we set env->error_code with what is supposed to be a
set of FPCR exception bit values.  However, if the set of float
exception flags we get back from softfloat for the conversion
includes a flag which is not one of the three we expect here
(invalid_cvti, invalid, inexact) then we will fall through the
if-ladder and set env->error_code to the unconverted softfloat
exception_flag value.  This will then cause us to take a spurious
exception.

This is harmless now, but when we add new floating point exception
flags to softfloat it will cause problems.  Add an else clause to the
if-ladder to make it ignore any float exception flags it doesn't care
about.

Specifically, without this fix, 'make check-tcg' will fail for Alpha
when the commit adding float_flag_input_denormal_used lands.


Fixes: aa3bad5b59e7 ("target/alpha: Use float64_to_int64_modulo for CVTTQ")
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2025-02-11 13:00:26 +00:00
Thomas Huth
66a1b4991c gitlab-ci.d/cirrus: Update the FreeBSD job to v14.2
The FreeBSD job started to fail since the 14-1 image disappeared
from the cloud. Update the job to v14.2 to fix it.

Message-ID: <20250211120817.35050-1-thuth@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2025-02-11 13:27:07 +01:00
Daniel P. Berrangé
b56e07ac1e gitlab: use new(ish) cirrus-vars command for creating config
Rather than a giant sed command with a hardcoded list of env var name,
we can now use the new(ish) cirrus-vars command that libvirt has added
to the 'cirrus-run' container.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-ID: <20241204194807.1472261-3-berrange@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2025-02-11 13:27:07 +01:00
Daniel P. Berrangé
7976879c4b gitlab: don't fail cirrus CI jobs when credits are exhausted
In the last week of the month we have often run out of credits on
Cirrus CI, which causes the jobs to fail, in turn causing the
overall pipeline to fail.

The cirrus-run tool can now detect the "out of credits" scenario
and exits with a code of '3'.  We can tell gitlab to treat this
exit code as special and mark the job as "warning" instead of
"failed". This allows the pipeline status overall to remain
green, when we have non-technical issues with Cirrus CI.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-ID: <20241204194807.1472261-2-berrange@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2025-02-11 13:27:07 +01:00
Cédric Le Goater
557277710a tests/functional: Add a ppc sam460ex test
The test sequence boots from kernel a sam460ex machine with a
virtio-net device to check PCI.

The buildroot is built with config :

  BR2_powerpc=y
  BR2_powerpc_440fp=y

and the kernel with the '44x/canyonlands' deconfig and virtio support.

Signed-off-by: Cédric Le Goater <clg@redhat.com>
Message-ID: <20250203092606.491933-1-clg@redhat.com>
[thuth: sort meson.build alphabetically]
Signed-off-by: Thomas Huth <thuth@redhat.com>
2025-02-11 13:27:07 +01:00