| Message ID | 20190423034959.13525-6-yamada.masahiro@socionext.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | compiler: allow all arches to enable CONFIG_OPTIMIZE_INLINING | expand |
Hi Masahiro, Masahiro Yamada <yamada.masahiro@socionext.com> wrote on Tue, 23 Apr 2019 12:49:53 +0900: > This prepares to move CONFIG_OPTIMIZE_INLINING from x86 to a common > place. We need to eliminate potential issues beforehand. > > Kbuild test robot has never reported -Wmaybe-uninitialized warning > for this probably because vf610_nfc_run() is inlined by the x86 > compiler's inlining heuristic. > > If CONFIG_OPTIMIZE_INLINING is enabled for a different architecture > and vf610_nfc_run() is not inlined, the following warning is reported: > > drivers/mtd/nand/raw/vf610_nfc.c: In function ‘vf610_nfc_cmd’: > drivers/mtd/nand/raw/vf610_nfc.c:455:3: warning: ‘offset’ may be used uninitialized in this function [-Wmaybe-uninitialized] > vf610_nfc_rd_from_sram(instr->ctx.data.buf.in + offset, > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > nfc->regs + NFC_MAIN_AREA(0) + offset, > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > trfr_sz, !nfc->data_access); > ~~~~~~~~~~~~~~~~~~~~~~~~~~~ IMHO this patch has no dependencies with this series. Would you mind sending it alone with the proper Fixes tag? > > Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> > --- > > Changes in v3: None > Changes in v2: > - split into a separate patch > > drivers/mtd/nand/raw/vf610_nfc.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/mtd/nand/raw/vf610_nfc.c b/drivers/mtd/nand/raw/vf610_nfc.c > index a662ca1970e5..19792d725ec2 100644 > --- a/drivers/mtd/nand/raw/vf610_nfc.c > +++ b/drivers/mtd/nand/raw/vf610_nfc.c > @@ -364,7 +364,7 @@ static int vf610_nfc_cmd(struct nand_chip *chip, > { > const struct nand_op_instr *instr; > struct vf610_nfc *nfc = chip_to_nfc(chip); > - int op_id = -1, trfr_sz = 0, offset; > + int op_id = -1, trfr_sz = 0, offset = 0; > u32 col = 0, row = 0, cmd1 = 0, cmd2 = 0, code = 0; > bool force8bit = false; > Thanks, Miquèl
Hi Miquel, On Thu, May 2, 2019 at 11:14 PM Miquel Raynal <miquel.raynal@bootlin.com> wrote: > > Hi Masahiro, > > Masahiro Yamada <yamada.masahiro@socionext.com> wrote on Tue, 23 Apr > 2019 12:49:53 +0900: > > > This prepares to move CONFIG_OPTIMIZE_INLINING from x86 to a common > > place. We need to eliminate potential issues beforehand. > > > > Kbuild test robot has never reported -Wmaybe-uninitialized warning > > for this probably because vf610_nfc_run() is inlined by the x86 > > compiler's inlining heuristic. > > > > If CONFIG_OPTIMIZE_INLINING is enabled for a different architecture > > and vf610_nfc_run() is not inlined, the following warning is reported: > > > > drivers/mtd/nand/raw/vf610_nfc.c: In function ‘vf610_nfc_cmd’: > > drivers/mtd/nand/raw/vf610_nfc.c:455:3: warning: ‘offset’ may be used uninitialized in this function [-Wmaybe-uninitialized] > > vf610_nfc_rd_from_sram(instr->ctx.data.buf.in + offset, > > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > nfc->regs + NFC_MAIN_AREA(0) + offset, > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > trfr_sz, !nfc->data_access); > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > IMHO this patch has no dependencies with this series. This patch is the prerequisite for 11/11. https://lore.kernel.org/patchwork/patch/1064959/ Without the correct patch order, the kbuild test robot reports the warning. > Would you mind sending it alone with the proper Fixes tag? I do not think Fixes is necessary. Nobody has noticed this potential issue before. Without 11/11, probably we cannot reproduce this warning. BTW, this series has been for a while in linux-next. > > > > > Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> > > --- > > > > Changes in v3: None > > Changes in v2: > > - split into a separate patch > > > > drivers/mtd/nand/raw/vf610_nfc.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/mtd/nand/raw/vf610_nfc.c b/drivers/mtd/nand/raw/vf610_nfc.c > > index a662ca1970e5..19792d725ec2 100644 > > --- a/drivers/mtd/nand/raw/vf610_nfc.c > > +++ b/drivers/mtd/nand/raw/vf610_nfc.c > > @@ -364,7 +364,7 @@ static int vf610_nfc_cmd(struct nand_chip *chip, > > { > > const struct nand_op_instr *instr; > > struct vf610_nfc *nfc = chip_to_nfc(chip); > > - int op_id = -1, trfr_sz = 0, offset; > > + int op_id = -1, trfr_sz = 0, offset = 0; > > u32 col = 0, row = 0, cmd1 = 0, cmd2 = 0, code = 0; > > bool force8bit = false; > > > > Thanks, > Miquèl > > ______________________________________________________ > Linux MTD discussion mailing list > http://lists.infradead.org/mailman/listinfo/linux-mtd/ -- Best Regards Masahiro Yamada
Hi Masahiro, Masahiro Yamada <yamada.masahiro@socionext.com> wrote on Fri, 3 May 2019 19:36:35 +0900: > Hi Miquel, > > On Thu, May 2, 2019 at 11:14 PM Miquel Raynal <miquel.raynal@bootlin.com> wrote: > > > > Hi Masahiro, > > > > Masahiro Yamada <yamada.masahiro@socionext.com> wrote on Tue, 23 Apr > > 2019 12:49:53 +0900: > > > > > This prepares to move CONFIG_OPTIMIZE_INLINING from x86 to a common > > > place. We need to eliminate potential issues beforehand. > > > > > > Kbuild test robot has never reported -Wmaybe-uninitialized warning > > > for this probably because vf610_nfc_run() is inlined by the x86 > > > compiler's inlining heuristic. > > > > > > If CONFIG_OPTIMIZE_INLINING is enabled for a different architecture > > > and vf610_nfc_run() is not inlined, the following warning is reported: > > > > > > drivers/mtd/nand/raw/vf610_nfc.c: In function ‘vf610_nfc_cmd’: > > > drivers/mtd/nand/raw/vf610_nfc.c:455:3: warning: ‘offset’ may be used uninitialized in this function [-Wmaybe-uninitialized] > > > vf610_nfc_rd_from_sram(instr->ctx.data.buf.in + offset, > > > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > > nfc->regs + NFC_MAIN_AREA(0) + offset, > > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > > trfr_sz, !nfc->data_access); > > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > > > IMHO this patch has no dependencies with this series. > > > This patch is the prerequisite for 11/11. > https://lore.kernel.org/patchwork/patch/1064959/ > > > Without the correct patch order, > the kbuild test robot reports the warning. > > > > Would you mind sending it alone with the proper Fixes tag? > > > I do not think Fixes is necessary. IMHO it is. Even if today the warning does not spawn, there is a real C error which might already be an issue. > > Nobody has noticed this potential issue before. > Without 11/11, probably we cannot reproduce this warning. > > > BTW, this series has been for a while in linux-next. Missed that. Ok, nevermind. Thanks, Miquèl
diff --git a/drivers/mtd/nand/raw/vf610_nfc.c b/drivers/mtd/nand/raw/vf610_nfc.c index a662ca1970e5..19792d725ec2 100644 --- a/drivers/mtd/nand/raw/vf610_nfc.c +++ b/drivers/mtd/nand/raw/vf610_nfc.c @@ -364,7 +364,7 @@ static int vf610_nfc_cmd(struct nand_chip *chip, { const struct nand_op_instr *instr; struct vf610_nfc *nfc = chip_to_nfc(chip); - int op_id = -1, trfr_sz = 0, offset; + int op_id = -1, trfr_sz = 0, offset = 0; u32 col = 0, row = 0, cmd1 = 0, cmd2 = 0, code = 0; bool force8bit = false;
This prepares to move CONFIG_OPTIMIZE_INLINING from x86 to a common place. We need to eliminate potential issues beforehand. Kbuild test robot has never reported -Wmaybe-uninitialized warning for this probably because vf610_nfc_run() is inlined by the x86 compiler's inlining heuristic. If CONFIG_OPTIMIZE_INLINING is enabled for a different architecture and vf610_nfc_run() is not inlined, the following warning is reported: drivers/mtd/nand/raw/vf610_nfc.c: In function ‘vf610_nfc_cmd’: drivers/mtd/nand/raw/vf610_nfc.c:455:3: warning: ‘offset’ may be used uninitialized in this function [-Wmaybe-uninitialized] vf610_nfc_rd_from_sram(instr->ctx.data.buf.in + offset, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ nfc->regs + NFC_MAIN_AREA(0) + offset, ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ trfr_sz, !nfc->data_access); ~~~~~~~~~~~~~~~~~~~~~~~~~~~ Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> --- Changes in v3: None Changes in v2: - split into a separate patch drivers/mtd/nand/raw/vf610_nfc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)