From b167d664414e7d4a5a7a7058bc4c7699f6e66d48 Mon Sep 17 00:00:00 2001 From: jianchunfu Date: Thu, 4 Aug 2022 15:57:46 +0800 Subject: [PATCH 6/9] target/ppc: enhance error report in kvmppc_read_int_cpu_dt() First and foremost, the function can't return '-1' when an error occurs because the return type is set to uint64_t. Let's fix that. After that, the function can't simply return 0 whether an error happened and call it a day. We must provide a way of letting callers know if the zero return is legitimate or due to an error. Add an Error pointer to kvmppc_read_int_cpu_dt() that will be filled with an appropriate error, if one occurs. Callers are then free to pass an Error pointer and handle it. Signed-off-by: jianchunfu --- target/ppc/kvm.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c index 63382256c3..d64d7c5b4a 100644 --- a/target/ppc/kvm.c +++ b/target/ppc/kvm.c @@ -1925,20 +1925,22 @@ static uint64_t kvmppc_read_int_dt(const char *filename, Error **errp) /* * Read a CPU node property from the host device tree that's a single - * integer (32-bit or 64-bit). Returns 0 if anything goes wrong - * (can't find or open the property, or doesn't understand the format) + * integer (32-bit or 64-bit). Returns 0 and set errp if anything goes + * wrong (can't find or open the property, or doesn't understand the + * format) */ -static uint64_t kvmppc_read_int_cpu_dt(const char *propname) +static uint64_t kvmppc_read_int_cpu_dt(const char *propname, Error **errp) { char buf[PATH_MAX], *tmp; uint64_t val; if (kvmppc_find_cpu_dt(buf, sizeof(buf))) { - return -1; + error_setg(errp, "Failed to read CPU property %s", propname); + return 0; } tmp = g_strdup_printf("%s/%s", buf, propname); - val = kvmppc_read_int_dt(tmp, NULL); + val = kvmppc_read_int_dt(tmp, errp); g_free(tmp); return val; @@ -1946,12 +1948,12 @@ static uint64_t kvmppc_read_int_cpu_dt(const char *propname) uint64_t kvmppc_get_clockfreq(void) { - return kvmppc_read_int_cpu_dt("clock-frequency"); + return kvmppc_read_int_cpu_dt("clock-frequency", NULL); } static int kvmppc_get_dec_bits(void) { - int nr_bits = kvmppc_read_int_cpu_dt("ibm,dec-bits"); + int nr_bits = kvmppc_read_int_cpu_dt("ibm,dec-bits", NULL); if (nr_bits > 0) { return nr_bits; @@ -2336,8 +2338,8 @@ static void alter_insns(uint64_t *word, uint64_t flags, bool on) static void kvmppc_host_cpu_class_init(ObjectClass *oc, void *data) { PowerPCCPUClass *pcc = POWERPC_CPU_CLASS(oc); - uint32_t dcache_size = kvmppc_read_int_cpu_dt("d-cache-size"); - uint32_t icache_size = kvmppc_read_int_cpu_dt("i-cache-size"); + uint32_t dcache_size = kvmppc_read_int_cpu_dt("d-cache-size", NULL); + uint32_t icache_size = kvmppc_read_int_cpu_dt("i-cache-size", NULL); /* Now fix up the class with information we can query from the host */ pcc->pvr = mfpvr(); -- 2.27.0