Re: [PATCH 5/7] EDAC, mce_amd: Convert to seq_buf

From: Steven Rostedt
Date: Fri Aug 25 2017 - 09:31:07 EST


On Fri, 25 Aug 2017 12:24:09 +0200
Borislav Petkov <bp@xxxxxxxxx> wrote:

> From: Borislav Petkov <bp@xxxxxxx>
>
> Convert the part which decodes the error description to the sequence
> buffer facility and thus save ourselves the many printk() invocations
> building the decoded string.
>
> Also, use a genpool for the string buffers to handle concurrent
> invocations (and atomic context).
>
> Signed-off-by: Borislav Petkov <bp@xxxxxxx>
> ---
> drivers/edac/mce_amd.c | 215 +++++++++++++++++++++++++++++--------------------
> 1 file changed, 127 insertions(+), 88 deletions(-)
>
> diff --git a/drivers/edac/mce_amd.c b/drivers/edac/mce_amd.c
> index a11a671c7a38..b7c1f8f7e871 100644
> --- a/drivers/edac/mce_amd.c
> +++ b/drivers/edac/mce_amd.c
> @@ -1,3 +1,5 @@
> +#include <linux/genalloc.h>
> +#include <linux/seq_buf.h>
> #include <linux/module.h>
> #include <linux/slab.h>
>
> @@ -34,6 +36,16 @@ void amd_unregister_ecc_decoder(void (*f)(int, struct mce *))
> }
> EXPORT_SYMBOL_GPL(amd_unregister_ecc_decoder);
>
> +/* 128 because, well, nice and round - two cachelines. */
> +#define ELEM_ORDER 7
> +#define ELEM_SIZE (1 << 7)
> +#define DEC_POOL_SIZE (2 * PAGE_SIZE)
> +
> +static char __err_buf[DEC_POOL_SIZE];
> +static struct gen_pool *dec_pool;
> +
> +static struct seq_buf sb;
> +
> /*
> * string representation for the different MCA reported error types, see F3x48
> * or MSR0000_0411.
> @@ -315,9 +327,9 @@ static bool f12h_mc0_mce(u16 ec, u8 xec)
> ret = true;
>
> if (ll == LL_L2)
> - pr_cont("during L1 linefill from L2.\n");
> + seq_buf_printf(&sb, "during L1 linefill from L2.\n");

Use seq_buf_puts()


> else if (ll == LL_L1)
> - pr_cont("Data/Tag %s error.\n", R4_MSG(ec));
> + seq_buf_printf(&sb, "Data/Tag %s error.\n", R4_MSG(ec));
> else
> ret = false;
> }
> @@ -327,7 +339,7 @@ static bool f12h_mc0_mce(u16 ec, u8 xec)
> static bool f10h_mc0_mce(u16 ec, u8 xec)
> {
> if (R4(ec) == R4_GEN && LL(ec) == LL_L1) {
> - pr_cont("during data scrub.\n");
> + seq_buf_printf(&sb, "during data scrub.\n");

seq_buf_puts()

> return true;
> }
> return f12h_mc0_mce(ec, xec);
> @@ -336,7 +348,7 @@ static bool f10h_mc0_mce(u16 ec, u8 xec)
> static bool k8_mc0_mce(u16 ec, u8 xec)
> {
> if (BUS_ERROR(ec)) {
> - pr_cont("during system linefill.\n");
> + seq_buf_printf(&sb, "during system linefill.\n");

seq_buf_puts()

> return true;
> }
>
> @@ -356,14 +368,14 @@ static bool cat_mc0_mce(u16 ec, u8 xec)
> switch (r4) {
> case R4_DRD:
> case R4_DWR:
> - pr_cont("Data/Tag parity error due to %s.\n",
> - (r4 == R4_DRD ? "load/hw prf" : "store"));
> + seq_buf_printf(&sb, "Data/Tag parity error due to %s.\n",
> + (r4 == R4_DRD ? "load/hw prf" : "store"));
> break;
> case R4_EVICT:
> - pr_cont("Copyback parity error on a tag miss.\n");
> + seq_buf_printf(&sb, "Copyback parity error on a tag miss.\n");

seq_buf_puts()

> break;
> case R4_SNOOP:
> - pr_cont("Tag parity error during snoop.\n");
> + seq_buf_printf(&sb, "Tag parity error during snoop.\n");

seq_buf_puts()

> break;
> default:
> ret = false;
> @@ -373,17 +385,17 @@ static bool cat_mc0_mce(u16 ec, u8 xec)
> if ((II(ec) != II_MEM && II(ec) != II_IO) || LL(ec) != LL_LG)
> return false;
>
> - pr_cont("System read data error on a ");
> + seq_buf_printf(&sb, "System read data error on a ");

seq_buf_puts()

>
> switch (r4) {
> case R4_RD:
> - pr_cont("TLB reload.\n");
> + seq_buf_printf(&sb, "TLB reload.\n");

seq_buf_puts()

> break;
> case R4_DWR:
> - pr_cont("store.\n");
> + seq_buf_printf(&sb, "store.\n");

seq_buf_puts()

> break;
> case R4_DRD:
> - pr_cont("load.\n");
> + seq_buf_printf(&sb, "load.\n");

seq_buf_puts()

> break;
> default:
> ret = false;
> @@ -403,28 +415,28 @@ static bool f15h_mc0_mce(u16 ec, u8 xec)
>
> switch (xec) {
> case 0x0:
> - pr_cont("Data Array access error.\n");
> + seq_buf_printf(&sb, "Data Array access error.\n");

seq_buf_puts()

> break;
>
> case 0x1:
> - pr_cont("UC error during a linefill from L2/NB.\n");
> + seq_buf_printf(&sb, "UC error during a linefill from L2/NB.\n");

seq_buf_puts()

> break;
>
> case 0x2:
> case 0x11:
> - pr_cont("STQ access error.\n");
> + seq_buf_printf(&sb, "STQ access error.\n");

seq_buf_puts()

> break;
>
> case 0x3:
> - pr_cont("SCB access error.\n");
> + seq_buf_printf(&sb, "SCB access error.\n");

seq_buf_puts()

> break;
>
> case 0x10:
> - pr_cont("Tag error.\n");
> + seq_buf_printf(&sb, "Tag error.\n");

seq_buf_puts()

> break;
>
> case 0x12:
> - pr_cont("LDQ access error.\n");
> + seq_buf_printf(&sb, "LDQ access error.\n");

seq_buf_puts()

> break;
>
> default:
> @@ -433,12 +445,12 @@ static bool f15h_mc0_mce(u16 ec, u8 xec)
> } else if (BUS_ERROR(ec)) {
>
> if (!xec)
> - pr_cont("System Read Data Error.\n");
> + seq_buf_printf(&sb, "System Read Data Error.\n");

seq_buf_puts()

> else
> - pr_cont(" Internal error condition type %d.\n", xec);
> + seq_buf_printf(&sb, " Internal error condition type %d.\n", xec);
> } else if (INT_ERROR(ec)) {
> if (xec <= 0x1f)
> - pr_cont("Hardware Assert.\n");
> + seq_buf_printf(&sb, "Hardware Assert.\n");

seq_buf_puts()

> else
> ret = false;
>
> @@ -453,13 +465,13 @@ static void decode_mc0_mce(struct mce *m)
> u16 ec = EC(m->status);
> u8 xec = XEC(m->status, xec_mask);
>
> - pr_emerg(HW_ERR "MC0 Error: ");
> + seq_buf_printf(&sb, HW_ERR "MC0 Error: ");

seq_buf_puts()

>
> /* TLB error signatures are the same across families */
> if (TLB_ERROR(ec)) {
> if (TT(ec) == TT_DATA) {
> - pr_cont("%s TLB %s.\n", LL_MSG(ec),
> - ((xec == 2) ? "locked miss"
> + seq_buf_printf(&sb, "%s TLB %s.\n", LL_MSG(ec),
> + ((xec == 2) ? "locked miss"
> : (xec ? "multimatch" : "parity")));
> return;
> }
> @@ -478,19 +490,19 @@ static bool k8_mc1_mce(u16 ec, u8 xec)
> return false;
>
> if (ll == 0x2)
> - pr_cont("during a linefill from L2.\n");
> + seq_buf_printf(&sb, "during a linefill from L2.\n");

seq_buf_puts()

> else if (ll == 0x1) {
> switch (R4(ec)) {
> case R4_IRD:
> - pr_cont("Parity error during data load.\n");
> + seq_buf_printf(&sb, "Parity error during data load.\n");

seq_buf_puts()

> break;
>
> case R4_EVICT:
> - pr_cont("Copyback Parity/Victim error.\n");
> + seq_buf_printf(&sb, "Copyback Parity/Victim error.\n");

seq_buf_puts()

> break;
>
> case R4_SNOOP:
> - pr_cont("Tag Snoop error.\n");
> + seq_buf_printf(&sb, "Tag Snoop error.\n");

seq_buf_puts()


OK, I'm getting tired of adding these ;-) You get the idea.

-- Steve

> break;
>
> default:
> @@ -515,13 +527,13 @@ static bool cat_mc1_mce(u16 ec, u8 xec)
> return false;
>
> if (r4 == R4_IRD)
> - pr_cont("Data/tag array parity error for a tag hit.\n");
> + seq_buf_printf(&sb, "Data/tag array parity error for a tag hit.\n");
> else if (r4 == R4_SNOOP)
> - pr_cont("Tag error during snoop/victimization.\n");
> + seq_buf_printf(&sb, "Tag error during snoop/victimization.\n");
> else if (xec == 0x0)
> - pr_cont("Tag parity error from victim castout.\n");
> + seq_buf_printf(&sb, "Tag parity error from victim castout.\n");
> else if (xec == 0x2)
> - pr_cont("Microcode patch RAM parity error.\n");
> + seq_buf_printf(&sb, "Microcode patch RAM parity error.\n");
> else
> ret = false;
>
> @@ -537,19 +549,19 @@ static bool f15h_mc1_mce(u16 ec, u8 xec)
>
> switch (xec) {
> case 0x0 ... 0xa:
> - pr_cont("%s.\n", f15h_mc1_mce_desc[xec]);
> + seq_buf_printf(&sb, "%s.\n", f15h_mc1_mce_desc[xec]);
> break;
>
> case 0xd:
> - pr_cont("%s.\n", f15h_mc1_mce_desc[xec-2]);
> + seq_buf_printf(&sb, "%s.\n", f15h_mc1_mce_desc[xec-2]);
> break;
>
> case 0x10:
> - pr_cont("%s.\n", f15h_mc1_mce_desc[xec-4]);
> + seq_buf_printf(&sb, "%s.\n", f15h_mc1_mce_desc[xec-4]);
> break;
>
> case 0x11 ... 0x15:
> - pr_cont("Decoder %s parity error.\n", f15h_mc1_mce_desc[xec-4]);
> + seq_buf_printf(&sb, "Decoder %s parity error.\n", f15h_mc1_mce_desc[xec-4]);
> break;
>
> default:
> @@ -563,18 +575,18 @@ static void decode_mc1_mce(struct mce *m)
> u16 ec = EC(m->status);
> u8 xec = XEC(m->status, xec_mask);
>
> - pr_emerg(HW_ERR "MC1 Error: ");
> + seq_buf_printf(&sb, HW_ERR "MC1 Error: ");
>
> if (TLB_ERROR(ec))
> - pr_cont("%s TLB %s.\n", LL_MSG(ec),
> - (xec ? "multimatch" : "parity error"));
> + seq_buf_printf(&sb, "%s TLB %s.\n", LL_MSG(ec),
> + (xec ? "multimatch" : "parity error"));
> else if (BUS_ERROR(ec)) {
> bool k8 = (boot_cpu_data.x86 == 0xf && (m->status & BIT_64(58)));
>
> - pr_cont("during %s.\n", (k8 ? "system linefill" : "NB data read"));
> + seq_buf_printf(&sb, "during %s.\n", (k8 ? "system linefill" : "NB data read"));
> } else if (INT_ERROR(ec)) {
> if (xec <= 0x3f)
> - pr_cont("Hardware Assert.\n");
> + seq_buf_printf(&sb, "Hardware Assert.\n");
> else
> goto wrong_mc1_mce;
> } else if (fam_ops->mc1_mce(ec, xec))
> @@ -593,27 +605,27 @@ static bool k8_mc2_mce(u16 ec, u8 xec)
> bool ret = true;
>
> if (xec == 0x1)
> - pr_cont(" in the write data buffers.\n");
> + seq_buf_printf(&sb, " in the write data buffers.\n");
> else if (xec == 0x3)
> - pr_cont(" in the victim data buffers.\n");
> + seq_buf_printf(&sb, " in the victim data buffers.\n");
> else if (xec == 0x2 && MEM_ERROR(ec))
> - pr_cont(": %s error in the L2 cache tags.\n", R4_MSG(ec));
> + seq_buf_printf(&sb, ": %s error in the L2 cache tags.\n", R4_MSG(ec));
> else if (xec == 0x0) {
> if (TLB_ERROR(ec))
> - pr_cont("%s error in a Page Descriptor Cache or Guest TLB.\n",
> - TT_MSG(ec));
> + seq_buf_printf(&sb, "%s error in a Page Descriptor Cache or Guest TLB.\n",
> + TT_MSG(ec));
> else if (BUS_ERROR(ec))
> - pr_cont(": %s/ECC error in data read from NB: %s.\n",
> - R4_MSG(ec), PP_MSG(ec));
> + seq_buf_printf(&sb, ": %s/ECC error in data read from NB: %s.\n",
> + R4_MSG(ec), PP_MSG(ec));
> else if (MEM_ERROR(ec)) {
> u8 r4 = R4(ec);
>
> if (r4 >= 0x7)
> - pr_cont(": %s error during data copyback.\n",
> - R4_MSG(ec));
> + seq_buf_printf(&sb, ": %s error during data copyback.\n",
> + R4_MSG(ec));
> else if (r4 <= 0x1)
> - pr_cont(": %s parity/ECC error during data "
> - "access from L2.\n", R4_MSG(ec));
> + seq_buf_printf(&sb,
> +": %s parity/ECC error during data access from L2.\n", R4_MSG(ec));
> else
> ret = false;
> } else
> @@ -630,24 +642,24 @@ static bool f15h_mc2_mce(u16 ec, u8 xec)
>
> if (TLB_ERROR(ec)) {
> if (xec == 0x0)
> - pr_cont("Data parity TLB read error.\n");
> + seq_buf_printf(&sb, "Data parity TLB read error.\n");
> else if (xec == 0x1)
> - pr_cont("Poison data provided for TLB fill.\n");
> + seq_buf_printf(&sb, "Poison data provided for TLB fill.\n");
> else
> ret = false;
> } else if (BUS_ERROR(ec)) {
> if (xec > 2)
> ret = false;
>
> - pr_cont("Error during attempted NB data read.\n");
> + seq_buf_printf(&sb, "Error during attempted NB data read.\n");
> } else if (MEM_ERROR(ec)) {
> switch (xec) {
> case 0x4 ... 0xc:
> - pr_cont("%s.\n", f15h_mc2_mce_desc[xec - 0x4]);
> + seq_buf_printf(&sb, "%s.\n", f15h_mc2_mce_desc[xec - 0x4]);
> break;
>
> case 0x10 ... 0x14:
> - pr_cont("%s.\n", f15h_mc2_mce_desc[xec - 0x7]);
> + seq_buf_printf(&sb, "%s.\n", f15h_mc2_mce_desc[xec - 0x7]);
> break;
>
> default:
> @@ -655,7 +667,7 @@ static bool f15h_mc2_mce(u16 ec, u8 xec)
> }
> } else if (INT_ERROR(ec)) {
> if (xec <= 0x3f)
> - pr_cont("Hardware Assert.\n");
> + seq_buf_printf(&sb, "Hardware Assert.\n");
> else
> ret = false;
> }
> @@ -672,29 +684,29 @@ static bool f16h_mc2_mce(u16 ec, u8 xec)
>
> switch (xec) {
> case 0x04 ... 0x05:
> - pr_cont("%cBUFF parity error.\n", (r4 == R4_RD) ? 'I' : 'O');
> + seq_buf_printf(&sb, "%cBUFF parity error.\n", (r4 == R4_RD) ? 'I' : 'O');
> break;
>
> case 0x09 ... 0x0b:
> case 0x0d ... 0x0f:
> - pr_cont("ECC error in L2 tag (%s).\n",
> - ((r4 == R4_GEN) ? "BankReq" :
> - ((r4 == R4_SNOOP) ? "Prb" : "Fill")));
> + seq_buf_printf(&sb, "ECC error in L2 tag (%s).\n",
> + ((r4 == R4_GEN) ? "BankReq" :
> + ((r4 == R4_SNOOP) ? "Prb" : "Fill")));
> break;
>
> case 0x10 ... 0x19:
> case 0x1b:
> - pr_cont("ECC error in L2 data array (%s).\n",
> - (((r4 == R4_RD) && !(xec & 0x3)) ? "Hit" :
> - ((r4 == R4_GEN) ? "Attr" :
> - ((r4 == R4_EVICT) ? "Vict" : "Fill"))));
> + seq_buf_printf(&sb, "ECC error in L2 data array (%s).\n",
> + (((r4 == R4_RD) && !(xec & 0x3)) ? "Hit" :
> + ((r4 == R4_GEN) ? "Attr" :
> + ((r4 == R4_EVICT) ? "Vict" : "Fill"))));
> break;
>
> case 0x1c ... 0x1d:
> case 0x1f:
> - pr_cont("Parity error in L2 attribute bits (%s).\n",
> - ((r4 == R4_RD) ? "Hit" :
> - ((r4 == R4_GEN) ? "Attr" : "Fill")));
> + seq_buf_printf(&sb, "Parity error in L2 attribute bits (%s).\n",
> + ((r4 == R4_RD) ? "Hit" :
> + ((r4 == R4_GEN) ? "Attr" : "Fill")));
> break;
>
> default:
> @@ -709,10 +721,10 @@ static void decode_mc2_mce(struct mce *m)
> u16 ec = EC(m->status);
> u8 xec = XEC(m->status, xec_mask);
>
> - pr_emerg(HW_ERR "MC2 Error: ");
> + seq_buf_printf(&sb, HW_ERR "MC2 Error: ");
>
> if (!fam_ops->mc2_mce(ec, xec))
> - pr_cont(HW_ERR "Corrupted MC2 MCE info?\n");
> + pr_emerg(HW_ERR "Corrupted MC2 MCE info?\n");
> }
>
> static void decode_mc3_mce(struct mce *m)
> @@ -726,7 +738,7 @@ static void decode_mc3_mce(struct mce *m)
> return;
> }
>
> - pr_emerg(HW_ERR "MC3 Error");
> + seq_buf_printf(&sb, HW_ERR "MC3 Error");
>
> if (xec == 0x0) {
> u8 r4 = R4(ec);
> @@ -734,7 +746,7 @@ static void decode_mc3_mce(struct mce *m)
> if (!BUS_ERROR(ec) || (r4 != R4_DRD && r4 != R4_DWR))
> goto wrong_mc3_mce;
>
> - pr_cont(" during %s.\n", R4_MSG(ec));
> + seq_buf_printf(&sb, " during %s.\n", R4_MSG(ec));
> } else
> goto wrong_mc3_mce;
>
> @@ -752,7 +764,7 @@ static void decode_mc4_mce(struct mce *m)
> u8 xec = XEC(m->status, 0x1f);
> u8 offset = 0;
>
> - pr_emerg(HW_ERR "MC4 Error (node %d): ", node_id);
> + seq_buf_printf(&sb, HW_ERR "MC4 Error (node %d): ", node_id);
>
> switch (xec) {
> case 0x0 ... 0xe:
> @@ -763,7 +775,7 @@ static void decode_mc4_mce(struct mce *m)
> if (fam == 0x11)
> goto wrong_mc4_mce;
>
> - pr_cont("%s.\n", mc4_mce_desc[xec]);
> + seq_buf_printf(&sb, "%s.\n", mc4_mce_desc[xec]);
>
> if (decode_dram_ecc)
> decode_dram_ecc(node_id, m);
> @@ -773,16 +785,16 @@ static void decode_mc4_mce(struct mce *m)
>
> case 0xf:
> if (TLB_ERROR(ec))
> - pr_cont("GART Table Walk data error.\n");
> + seq_buf_printf(&sb, "GART Table Walk data error.\n");
> else if (BUS_ERROR(ec))
> - pr_cont("DMA Exclusion Vector Table Walk error.\n");
> + seq_buf_printf(&sb, "DMA Exclusion Vector Table Walk error.\n");
> else
> goto wrong_mc4_mce;
> return;
>
> case 0x19:
> if (fam == 0x15 || fam == 0x16)
> - pr_cont("Compute Unit Data Error.\n");
> + seq_buf_printf(&sb, "Compute Unit Data Error.\n");
> else
> goto wrong_mc4_mce;
> return;
> @@ -795,7 +807,7 @@ static void decode_mc4_mce(struct mce *m)
> goto wrong_mc4_mce;
> }
>
> - pr_cont("%s.\n", mc4_mce_desc[xec - offset]);
> + seq_buf_printf(&sb, "%s.\n", mc4_mce_desc[xec - offset]);
> return;
>
> wrong_mc4_mce:
> @@ -811,20 +823,20 @@ static void decode_mc5_mce(struct mce *m)
> if (fam == 0xf || fam == 0x11)
> goto wrong_mc5_mce;
>
> - pr_emerg(HW_ERR "MC5 Error: ");
> + seq_buf_printf(&sb, HW_ERR "MC5 Error: ");
>
> if (INT_ERROR(ec)) {
> if (xec <= 0x1f) {
> - pr_cont("Hardware Assert.\n");
> + seq_buf_printf(&sb, "Hardware Assert.\n");
> return;
> } else
> goto wrong_mc5_mce;
> }
>
> if (xec == 0x0 || xec == 0xc)
> - pr_cont("%s.\n", mc5_mce_desc[xec]);
> + seq_buf_printf(&sb, "%s.\n", mc5_mce_desc[xec]);
> else if (xec <= 0xd)
> - pr_cont("%s parity error.\n", mc5_mce_desc[xec]);
> + seq_buf_printf(&sb, "%s parity error.\n", mc5_mce_desc[xec]);
> else
> goto wrong_mc5_mce;
>
> @@ -838,12 +850,12 @@ static void decode_mc6_mce(struct mce *m)
> {
> u8 xec = XEC(m->status, xec_mask);
>
> - pr_emerg(HW_ERR "MC6 Error: ");
> + seq_buf_printf(&sb, HW_ERR "MC6 Error: ");
>
> if (xec > 0x5)
> goto wrong_mc6_mce;
>
> - pr_cont("%s parity error.\n", mc6_mce_desc[xec]);
> + seq_buf_printf(&sb, "%s parity error.\n", mc6_mce_desc[xec]);
> return;
>
> wrong_mc6_mce:
> @@ -871,13 +883,13 @@ static void decode_smca_error(struct mce *m)
> bank_type = hwid->bank_type;
> ip_name = smca_get_long_name(bank_type);
>
> - pr_emerg(HW_ERR "%s Extended Error Code: %d\n", ip_name, xec);
> + seq_buf_printf(&sb, HW_ERR "%s Extended Error Code: %d\n", ip_name, xec);
>
> /* Only print the decode of valid error codes */
> if (xec < smca_mce_descs[bank_type].num_descs &&
> (hwid->xec_bitmap & BIT_ULL(xec))) {
> - pr_emerg(HW_ERR "%s Error: ", ip_name);
> - pr_cont("%s.\n", smca_mce_descs[bank_type].descs[xec]);
> + seq_buf_printf(&sb, HW_ERR "%s Error: ", ip_name);
> + seq_buf_printf(&sb, "%s.\n", smca_mce_descs[bank_type].descs[xec]);
> }
>
> if (bank_type == SMCA_UMC && xec == 0 && decode_dram_ecc)
> @@ -944,10 +956,21 @@ amd_decode_mce(struct notifier_block *nb, unsigned long val, void *data)
> struct mce *m = (struct mce *)data;
> unsigned int fam = x86_family(m->cpuid);
> int ecc;
> + char *dec_buf;
>
> if (amd_filter_mce(m))
> return NOTIFY_STOP;
>
> + dec_buf = (void *)gen_pool_alloc(dec_pool, ELEM_SIZE);
> + if (!dec_buf) {
> + pr_warn("Decode buffer full!\n");
> + return NOTIFY_STOP;
> + }
> +
> + /* \0 terminated */
> + seq_buf_init(&sb, dec_buf, ELEM_SIZE);
> + seq_buf_clear_buf(&sb);
> +
> pr_emerg(HW_ERR "%s\n", decode_error_status(m));
>
> pr_emerg(HW_ERR "CPU:%d (%x:%x:%x) MC%d_STATUS[%s|%s|%s|%s|%s",
> @@ -1044,6 +1067,10 @@ amd_decode_mce(struct notifier_block *nb, unsigned long val, void *data)
> err_code:
> amd_decode_err_code(m->status & 0xffff);
>
> + pr_emerg("%.*s\n", (int)sb.len, sb.buffer);
> +
> + gen_pool_free(dec_pool, (unsigned long)dec_buf, ELEM_SIZE);
> +
> return NOTIFY_STOP;
> }
>
> @@ -1055,6 +1082,7 @@ static struct notifier_block amd_mce_dec_nb = {
> static int __init mce_amd_init(void)
> {
> struct cpuinfo_x86 *c = &boot_cpu_data;
> + int ret;
>
> if (c->x86_vendor != X86_VENDOR_AMD)
> return -ENODEV;
> @@ -1122,6 +1150,16 @@ static int __init mce_amd_init(void)
> goto err_out;
> }
>
> + dec_pool = gen_pool_create(ELEM_ORDER, -1);
> + if (!dec_pool)
> + goto err_out;
> +
> + ret = gen_pool_add(dec_pool, (unsigned long)__err_buf, DEC_POOL_SIZE, -1);
> + if (ret) {
> + gen_pool_destroy(dec_pool);
> + goto err_out;
> + }
> +
> pr_info("MCE: In-kernel MCE decoding enabled.\n");
>
> mce_register_decode_chain(&amd_mce_dec_nb);
> @@ -1140,6 +1178,7 @@ static void __exit mce_amd_exit(void)
> {
> mce_unregister_decode_chain(&amd_mce_dec_nb);
> kfree(fam_ops);
> + gen_pool_destroy(dec_pool);
> }
>
> MODULE_DESCRIPTION("AMD MCE decoder");